E2004(auto cad)

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MALAYSIA POLYTECHNICS

MINISTRY OF EDUCATION

MODULE E 2004

COMPUTER AIDED DESIGN

IDRIS BIN KAMARUDDIN (PSA) SHALIZA BT SHAHRIL (PSA)

BIODATA OF MODULE WRITERS E2004 COMPUTER AIDED DESIGN

Name : Idris Bin Kamaruddin Address : Electrical Engineering Department Politeknik Sultan Salahuddin Abdul Aziz Shah, Persiaran Usahawan, Seksyen U1, 40150 Shah Alam, Selangor. Telephone No. : 03-55691901 ext.6020 e-mail : [email protected] / [email protected] : B.Eng Electrical ( Mechatronic )– (UTM) Position : Lecturer

Name : Shaliza Bt Shahril Address : Electrical Engineering Department Politeknik Sultan Salahuddin Abdul Aziz Shah, Persiaran Usahawan, Seksyen U, 40150 Shah Alam, Selangor. Telephone No. : 03-55691901 ext.6020 e-mail : [email protected] Qualifications : Diploma Electrical Engineering & Education.( ITTHO- UTM )

Position : Polytechnic Lecturer PROOF READER

Name : Khairul Bariah Bt Takrim Address : No.2, Lorong Sungai Isap Damai 8, 2515, Kuantan, Pahang. ( Politeknik Sultan Ahmad Shah ) Telephone No. : 019-9672922 e-mail : Qualifications : MA TESL, BA Linguistics Position : Lecturer

mailto:[email protected]

What Do You Think Of This Module?

Title of Module: _______________________ Module Code : ___________ Student’s Name: _______________________ Registration No. : ___________ Course : ____________________________________ Module Writers: ______________________________ Please use the following scale for your evaluation:

4 Strongly Agree 3 Agree 2 Disagree 1 Strongly Disagree

Instruction : Please √ on the space provided.

No. How much do you agree with the following statements? SCALE

A. FORMAT 1 2 3 4 1 The pages are organized in an interesting manner. 2 The font size makes it easy for me to read the module.

3 The size and types of pictures and charts used are suitable for the input.

4 The pictures and charts are easy to read and understand. 5 The tables used are well-organised and easy to understand. 6 The arrangement of the Input makes it easy for me to follow. 7 All the instructions are displayed clearly. B. CONTENTS 1 2 3 4

8 I understand all the objectives clearly. 9 I understand the ideas conveyed.

10 The ideas are presented in an interesting manner. 11 All the instructions are easy to understand. 12 I can carry out the instructions in this module. 13 I can answer the questions in the activities easily. 14 I can answer the questions in the self-assessment. 15 The feedback section can help me identify my mistakes. 16 The language used is easy to understand. 17 The way the module is written makes it interesting to read. 18 I can follow this module easily. 19 Each unit helps me understand the topic better.

20 I have become more interested in the subject after using this module.

CURRICULUM GRID

The curriculum grid of this module is based on the curriculum used by Malaysian polytechnics.

No. TOPIC UNIT Total Hours

1

Introduction To CAD

1

3

2

Methods to Entering Command and Data Input

2 6

3

Drawing Aids, Drawing Limits and Display Control

3

3

4

Draw Command

4

9

5

Modify Command

5

6

6 Text,Dtext and Textstyles

6 6

7 Dimensioning 7 3

8 Linetype, Layer and Block

8 3

9 Printing 9 3

UNIT 1 INTRODUCTION TO CAD

1.1 Introduction 1.1.1 CAD Definition

1.1.2 Systems requirement 1.1.3 The list of other CAD packages 1.1.4 Advantages of using CAD

1.2 Getting started

1.2.1 Introducing CAD for windows.

UNIT 2 METHODS TO ENTERING COMMAND AND DATA INPUT 1.1 How to begin command 1.2 Creating drawing by using Coordinate Entry.

UNIT 3 DRAWING AIDS, DRAWING LIMITS AND DISPLAY

CONTROL 3.1 Describing drawing aids command:

3.1.1 Snap 3.1.2 Ortho 3.1.3 Grid 3.1.4 Object Snap

3.2 Drawing Limits setup. 3.3 Explaining display control and others display commands

3.3.1 Zoom 3.3.2 Pan 3.3.3 Redraw 3.3.4 Regen

UNIT 4 DRAW COMMANDS

4.1 Identifying the specification of draw commands. 4.1. 1 Lines 4.1. 2 Arc

4.1. 3 Circles 4.1. 4 Ellipse 4.1. 5 Polygon 4.1. 6 Point 4.1. 7 Polyline 4.1. 8 Solid 4.1. 9 Donut

4.2 Drawing simple electronics component, schematic and PCB diagram by using draw commands.

UNIT 5 MODIFY COMMANDS

5.1 Describing the using of edit commands

5.1.1 Erase 5.1.2 Move 5.1.3 Rotate 5.1.4 Trim 5.1.5 Scale 5.1.6 Mirror 5.1.7 Array 5.1.8 Stretch 5.1.9 Extend 5.1.10 Fillet 5.1.11 Chamfer 5.1.12 Offset 5.1.13 Divide 5.1.14 Measure 5.1.15 Change 5.1.16 Pedit

UNIT 6 TEXT, DTEXT AND TEXTSTYLES

6.1 Describing TEXT and DTEXT command. 6.1.1 Justify Text 6.1.2 Font 6.1.3 Textstyle Operations.

UNIT 7 DIMENSIONING

7.1 Benefit of using dimension. 7.2 Describing of Dim Style and Dimupdate 7.3 Types of dimension.

7.3.1 Linear 7.3.2 Aligned 7.3.3 Angular 7.3.4 Diameter 7.3.5 Radius

UNIT 8 LINETYPE, LAYER AND BLOCK

8.1 Type of line regarding with drawing needed. 8.1.1 Load and setting type of lines

8.2 Layer

8.2.1 Introduction of Layer 8.2.2 Layer Commands 8.2.3 Layer Control by using dialog box 8.2.4 Create a drawing after layer setting.

8.3 Block and Wblock

8.3.1 Describing of block and Wblock, insert, Minsert, explode, and attribute.

UNIT 9 PRINTING 9.1 Printing Command 9.2 Print / Plot Configuration

.

MODULE GUIDELINES

To achieve maximum benefits in using this module, students must follow the instructions carefully and complete all the activities. 1. This module is divided into 16 units. 2. Each page is numbered according to the subject code, unit and page number.

E2004 / UNIT 1 / 5

Subject Unit 1 Page Number 5 3. The general and specific objectives are given at the beginning of each unit. 4. The activities in each unit are arranged in a sequential order and the

following symbols are given:

OBJECTIVES The general and specific objectives for each learning topic are stated in this section.

INPUT

This section introduces the subject matter that you are going to learn.

ACTIVITIES The activities in this section test your understanding of the subject matter. You have to complete this section by following the instructions

FEEDBACK Answers to the questions in the activity section are given here

SELF-ASSESSMENT Self-assessment evaluates your understanding of each unit.

FEEDBACK OF SELF-ASSESSMENT This section contains answers to the activities in the self-assessment. .

5. You have to follow the units in sequence. 6. You may proceed to the next unit after successfully completing the unit and

you are confident of your achievement.

GENERAL AIMS This module is prepared for students in the second semester who are following the Certificate/Diploma programmes in Malaysian Polytechnics. It aims to expose students to the Computer Aided Design concept in each unit and to lead them towards self-directed learning or with guidance from their lecturers.

PREREQUISITE SKILLS AND KNOWLEDGE The prerequisites of this module is at least a pass in SPM. GENERAL OBJECTIVES At the end of this module, students should be able to:

1. Describe the CAD definition, system requirement and advantage of using CAD. 2. Get started with AutoCAD. 3. Enter command and data input 4. Use draw command to make simple drawing. 5. Use draw aids command to make drawing easier. 6. Learn to use draw limits. 7. Learn to use important editing command. 8. Use display control. 9. Learn how to place text on a drawing. 10. Learn how to use dimensioning. 11. Use linetype in the drawing. 12. Learn how to use layer to control display of the drawing. 13. Learn to make and insert blocks. 14. Set the printing to print drawing.

TEACHING AIDS AND RESOURCES NEEDED

1. Computer 2. AutoCAD ( R14, R2000 or 2002 ) Software.

REFERENCES

1. James A.Leach ( 1998 ) – AutoCAD 14 Instructor; McGraw Hill Company.

2. KnowledgeworksTM ( 1998 ) – AutoCAD R14 Fundamentals; Autodesk Press

3. Alan J.Kalameja ( 1995 ) – The Autocad Tutor For Engineering Graphics-Release 12 and 13; Autodesk Press.

4. Bill Burehard, David Pitzer, Francis Soen ( 1998 ) – Inside Autocad 14, Limited Edition; New Rider Publishing, Indianapolis, Indiana.

5. Alan T.H Khoo ( 2002 ) – Step by Step AutoCADLT, Volume 1: The Basic; Federal Publications Sdn. Bhd, Shah Alam.

E2004/1/1 INTRODUCTION TO CAD

UNIT 1

INTRODUCTION TO CAD

OBJECTIVES

General Objective : To understand the function of CAD and how to begin using

AutoCAD

Specific Objectives : At the end of the unit you should be able to:

Explain CAD.

Identify system requirement needed to run the CAD program.

List other CAD packages.

Explain the advantages of using CAD compared to conventional drawing.

Start AutoCAD to begin drawing.

Use menus, dialog box and toolbars.

Save and exit from AutoCAD drawing.


INPUT 1a

1.0 DEFINITION OF CAD CAD is an acronym for Computer Aided Design or Computer Aided Drafting. CAD allows you to accomplish design and drafting activities using a computer. We can use CAD to draw a building plan, circuit diagram, chart, 3D object and more. Design is a broad field involving the process of making ideas into a real product or system. The design process requires repeated refinement of ideas until a solution results – a manufactured product or constructed system. Traditionally, design involves the use of sketches, drawings, renderings, 2-dimensional and 3-dimensional models, prototypes, testing, analysis, and documentation. Drafting is generally known as the production of drawing that is used to document a design for manufacturing or construction or to archive the design. CAD is a tool that can be used to design and draft activities. CAD can be used to make “rough” ideas drawing, although it is more suited to create accurate finished drawing and rendering. CAD can be used to create a 2-dimensional or 3-dimensional computer model or system for further analysis and testing by other computer programs. In addition, CAD can be used to supply manufacturing equipment such as lathes, mills, laser cutter, or rapid prototyping equipment with numerical data to manufacture a product. CAD is also used to create the 2-dimensional documentation drawing for communicating and archiving the design. The tangible result of CAD activity is usually a drawing generated by a plotter or printer but can be a rendering of a model or numeric data in binary usually saved to magnetic or optical device such as a diskette, hard disk, tape or CD.


1.1 SYSTEM REQUIREMENT.

The following list consists of recommended hardware and software required for proper operation using CAD software.

• Windows NT 3.51 or 4.0 or Windows 95 and the latest version. • 32 MB of RAM. • 50 MB of hard disk space. • 10 MB additional RAM for each concurrent CAD session.

1.2 THE LIST OF OTHER CAD PACKAGE

There are many CAD packages that we can use to make a drawing. Each CAD package has an advantage to make drawing easier. Example of the packages are listed below;

• AutoCAD • Catiar • AutoCADLT • MasterCAM • PSPICE • AutoSketch

However, with the advancement of technology, CAD program has undergone changes and updated to meet the need of users.

1.3 ADVANTAGES OF USING AUTOCAD

Although there are many methods used to design and draft activities, CAD offers the following advantages over other methods in many cases:

• Improving productivity, capability and accuracy. • Faster editing, reviewing and designing.


• Improving quality of end product. • Save storage for drawing.

1.3.1 Improving productivity, capability and accuracy.

Simple drawing created manually requires lesser time than larger and more complex drawings, particularly those involving similar shapes or repetitive operations. It may take some time to set up the first drawing and create some of the initial geometry, but any of the existing geometry or drawing setup can be easily duplicated in the current or for new drawings. As CAD and the associated technology advance and software are becoming more interconnected, more productive developments are available. For example, it is possible to make a change to a 3-dimensional model that automatically causes a related change in the linked 2-dimensional engineering drawing. One of the main advantages of these technological advances is productivity. When you draw with CAD system, the graphical elements, such as lines, arc, and circles are stored in the Cad file as a numeric data. CAD systems store that numeric data with great precision. For example, AutoCAD stores values with fourteen signification digits. The value 1 for example, is stored in scientific notation as the equivalent of 1.0000000000000. This precision provides you with the ability to create design and drawing that are 100% accurate for almost every case.

1.3.2 Faster editing, reviewing and designing.

Making changes to a CAD file known as editing is generally much faster than making changes to a traditional manual drawing. Since all the graphics elements in a CAD drawing are stored, only the affected components of the design or drawing need to be altered, and the drawing can be plotted or printed again or converted to other formats. It can save our time to produce a new drawing.


1.3.3 Improving quality of end product.

The quality of end product is improved because during the development, we use accurate measurement without any confusion.

1.3.4 Save of storage With conventional method we use drawing paper as a media to save our file. If we have lot of drawing, more space is needed. This storage problem can be solved by using CAD drawing. We just need an electronic storage element such as hard disk or diskette to save a thousand drawing file.

As a student, learning AutoCAD, as opposed to learning another CAD

software product, give you a higher probability of using your skills in industry. Likewise, there are employers who use AutoCAD than any other single CAD system. In addition, learning AutoCAD is a first CAD system gives you a good foundation for learning other CAD packages because many concepts and commands introduced by AutoCAD are utilized by other systems. In some cases, an AutoCAD feature becomes industry standards. The .DXF file format, for example, was introduced by AutoDesk and has become an industry standard for CAD file conversion between systems.


ACTIVITY 1a

FILL IN THE BLANK.

1.1 What is the definition of CAD? List its main function. ___________________________________________________________________________________________________________________________________________________________________________________________________

1.2 List all the CAD packages that you know of. ___________________________________________________________________________________________________________________________________________________________________________________________________

1.3 List the advantages of using CAD compared to conventional methods.

____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________


FEEDBACK TO ACTIVITY 1a

ANSWERS.

1.1 CAD is an acronym for Computer Aided Design or Computer Aided Drafting. CAD allows you to accomplish design and drafting activities using a computer. We can use CAD to draw a building plan, circuit diagram, chart, 3D object and more. (Refer to input 1a page 2 ) 1.2 There are many CAD packages that we can use to make a drawing. Each CAD package has an advantage to make drawing easier. Example of the packages are listed below;

a. AutoCAD b. Catiar c. AutoCADLT d. MasterCAM e. PSPICE f. AutoSketch

1.3. Although there are many methods used to design and draft activities, CAD offers the

following advantages over other methods in many cases: • Improving productivity, capability and accuracy. • Faster editing, reviewing and designing. • Improving quality of end product. • Save storage for drawing.


INPUT 1b

1.4 STARTING AUTOCAD

In this module, we use AutoCAD R14 package. We can use another AutoCAD version because the basic drawing is similar. Assuming that AutoCAD has been installed and configured properly for your system, you are ready to begin using AutoCAD. To start AutoCAD using any Windows, double click on the icon on the desktop as shown below.

Figure 1.1: AutoCAD R14 Icon If the icon does not appear on the desktop, press the ‘Start’ button,

highlight ‘Programs’, and search for ‘AutoCAD R14’ in the menu. From the list displayed, select ‘AutoCAD R14’.

Figure 1.2: Start AutoCAD from Start button


1.4.1 Start Up Dialog Box

When you start AutoCAD, the ‘Start Up’ dialog box appears. This dialog box includes several tools to help you open an existing drawing or set up a new drawing.

Figure 1.3: Start Up dialog box

The following is the content of the instructions for the ‘Start Up’ dialog box as it explains the purpose of the first four buttons.

The button on the left determine how you begin a drawing “ Use a Wizard ” - lead through setting up a drawing “ Use a Template ” - start a drawing based on the template

“ Start from Scratch ”- begin drawing quickly using default English or Metric settings

“ Open a Drawing ” - Open an existing drawing

USE A WIZARD If you want to set up a drawing using a dialog box, choose ‘Use a Wizard’. You can choose from two wizards: ‘Quick Setup’ and ‘Advanced Setup’.


‘Quick Setup.’

Choose the Quick Setup wizard to set up the drawing area and change settings, such as text height and snap spacing, to an appropriate scale. With the Quick Setup wizard, you establish basic settings that help define the units of measure and drawing area. These settings include the basic unit type (such as architectural, decimal, engineering, fractional, or scientific units) to be used for display and plotting.

You also specify the width and length of the drawing area, and thereby establish the drawing's boundaries, called limits. The area within these limits defines the final plotted sheet size. After you accept the settings, the drawing session will begin.

Step 1: Units

Select the format in which you want to display units of measure.

Select the format in which you want to enter and display coordinates and measurements. Several measurement styles are available in AutoCAD. Two of them, Engineering and Architectural, have a specific base unit (inches) assigned to them. You can choose from other measurement styles that can represent any convenient unit of measurement:

Decimal. - Select to display measurements in decimal notation. Engineering. - Select to display measurements in feet and decimal

inches. Architectural.- Select to display measurements in feet, inches, and

fractional inches. Frictional - Select to display measurements in mixed number

(integer and fractional) notation. Scientific. - Select to display measurements in scientific notation

(numbers expressed in the form of the product of a decimal number between 0 and 10 and a power of 10).


Figure 1.4 : Quick Setup box for step 1.

Step 2: Area

Enter the approximate width and length in full-scale units of what you plan to draw. This limits the area of the drawing covered by grid dots when the grid is turned on. It also adjusts several default settings, such as text height, linetype scaling, and snap distance, to convenient values. You can also adjust these settings, individually, from the Format menu later in the drawing session.

Figure 1.5 : Quick Setup box for step 2.


‘Advanced Setup.’

Choose the Advanced Setup wizard to set up the drawing area and change settings, such as text height and snap spacing, to an appropriate scale. You can also establish basic layout features.

Step 1: Units

Select the format in which you want to enter and display coordinates

and measurements. Several measurement styles are available in AutoCAD. Two of them, Engineering and Architectural, have a specific base unit assigned to them (inches). You can choose from other measurement styles that can represent any convenient unit of measurement:

Figure 1.6: Advanced Setup box for step 1

The precision that you specify controls the number of decimal places or fractional size to which you want linear measurements displayed. Step 2: Angles Select the format in which you want to enter and display angles: Decimal Degrees. Select to enter and display partial degrees as decimals. Deg/Min/Sec. Select to enter and display partial degrees as minutes

and seconds. Grads. Select to enter and display angles as grads.

Radians. Select to enter and display angles as radians. Surveyor. Select to enter and display angles in surveyor units.


Figure 1.7: Advanced Setup for step 2

Step 3: Angle Measure

Select the direction of the zero angles for the entry of angles:

Figure 1.8: Advanced Setup box for step 3.

East. Select to specify the compass direction east as the zero angle. North. Select to specify the compass direction north as the zero angle. West. Select to specify the compass direction west as the zero angle. South. Select to specify the compass direction south as the zero angle.


Other. Select to specify a direction different from the points of the compass as the zero angle.

Step 4: Angle Direction

Select the direction to enter and display positive angle values:

counterclockwise or clockwise.

Figure 1.9: Advanced Setup Box for step 4

Step 5: Area

Enter the approximate width and length of what you plan to draw in full-scale units. This limits the area of the drawing covered by grid dots when the grid is turned on. It also adjusts several default settings, such as text height, linetype scaling, and snap distance, to convenient values. You can also adjust these settings, individually, from the Format menu later in the drawing session.


Figure 1.10 : Advanced Setup box for Step 5

Step 6: Title Block

Select the description of an AutoCAD drawing file of a title block to

insert as a symbol in your new drawing. You can add or remove drawing files of title blocks from the list with the ‘Add and Remove’ buttons.

Figure 1.11: Advanced Setup box for Step 6 Step 7: Layout

Select Yes to use advanced paper space layout capabilities in AutoCAD. Paper space is often used to create complex multiple-view


drawings. Select No to use model space only. If you select ‘Yes’ to use paper space, you have three choices of where you want to begin working.

Figure 1.12: Advanced Setup box for step 7

USE A TEMPLATE. If you want to start a drawing based on a template drawing, choose Use a Template.

Figure 1.13 : Create New Drawing using Template

Template Drawing is a drawing file that you can use as a starting point for new drawings. It stores all the settings for a drawing and may also include


predefined layers, dimension styles, and views. Template drawings are distinguished from other drawing files by a different file extension, .dwt. They are normally kept in the template directory. Several template drawings are included with AutoCAD. You can make additional template drawings by changing the extensions of drawing file names to have a .dwt extension.

START FROM SCRATCH

If you want to begin drawing quickly using default English or metric settings, choose Start from Scratch.

Figure 1.14 : Create New Drawing box using Start From Scratch

From the Select Default setting field, we can choose either English or Metric setting. English - Unit measurement is in traditional setting ( Inches ) Metric - Unit measurement is in standard setting ( MM )

1.5 AUTOCAD R14 DRAWING SCREEN

Below are the standard screens for AutoCAD R14. We can adjust the screen weather to add or remove some toolbar or change the toolbar or resize the screen


arrangement. In a standard AutoCAD R14, we can see the ‘Menu Bar’, ‘Toolbar’, ‘Layer Status Windows’, ‘Command Line’, ‘Status Line’, ‘Drawing Area’ and ‘Cursor Pointing’.

Menu Bar

Toolbars

Layer Status Window

Crosshair Cursor

Drawing Area

Status Line Command Line

Figure 1.15 : AutoCAD Drawing Screen

Toolbars AutoCAD R14 provides a variety of toolbars. Each toolbar contains a number of icon buttons that can be selected to invoke command.

Menu Bars These menus provide an alternative method of accessing command and dialog boxes other than the Command Prompt or a toolbars button. They are termed pull-down menus because when you choose one with your left mouse button, the menu is displayed beneath its title, as if you were pulling the menu down from its title.


Pull-Down Menu

Figure 1.16: Pull-Down Menu

Command Line The command line is a docked or floating window where you can enter names or command and where AutoCAD displays prompts and messages. Layer Status Window Layer status window shows the current layer setting. Status Line The status line is a set of informative words or symbols that gives the status of the drawing aids. The following drawing aids can be toggled on or off by double-clicking on the desired word or by using Function keys or Ctrl key sequences.

1.6 GETTING TOOLBARS FROM PULL DOWN MENU

We can use toolbars to perform the desired command like ‘line’, ‘circles’ and other. By default there are four toolbars that appear in the AutoCAD screen. To display another toolbar, we can access the ‘Toolbars’ dialog box in the following ways; Toolbar : ‘Right clicking any currently visible toolbar’ Menu : View>Toolbar Command : toolbar


The toolbar dialog box is displayed, as shown in the following figure:

Figure 1.17: Toolbar Setting Box

Choose any of the toolbar checkboxes displays the toolbar. The toolbar can then be moved anywhere in the application window by selecting the title bar and dragging the toolbar to a location.

1.7 SAVING FILE AND EXIT FROM AUTOCAD

AutoCAD uses different file saving command that protect your work by storing the existing drawing status to a named file in a directory. Saving your work is very important because if there is a power failure, all of your work saved prior to the problem will be usable. Various file saving commands are used to store drawing information. These command include SAVE, SAVE AS and QSAVE.

The SAVE command saves the drawing with the current filename or a specified name when saved the first time. We can get the command with the following ways

Menu : File>Save Command : SAVE

The SAVE AS command saves unnamed drawings with a filename, or saves the current drawing with a different name.


The QSAVE command saves currently named drawing one at a time without requesting a filename

Toolbar : Menu : File > Save Command : QSAVE

Use the following steps to save unnamed drawing

1. Toolbars : ( If we click this button for the first time, the Save Drawing As box will appear )

Menu : File> Save Command : SAVE

2. When the Save Drawing As appears, enter the name of the drawing in

file name field. ( the file extension is not required)

Figure 1.18: ‘Save Drawing As’ box

After saving the file we can continue or exit the AutoCAD application. To exit from AutoCAD, use the following method; 1. Click at the very right upper button of the screen

Menu : File>Exit Command : EXIT


ACTIVITY 1b

EXERCISES.

1.4 Starting AutoCAD by clicking the ‘AutoCAD R14 shortcut icon’ or

‘AutoCAD R14’ from the ‘programs menu’. If the start up dialog box appears, select ‘start from scratch’. Choose ‘English’ as the default setting, and click the ‘OK’ button. At the AutoCAD screen, name toolbars and menus when we moved the cursor around the screen without clicking.

1.5 Draw a line by typing ‘L’ at the ‘command line’. Click the cursor at the

drawing area and move it to other point. Save your drawing and name it ‘exercise1’.

1.6 Exit AutoCAD by selecting the exit option from the ‘pull down menu’ or

click the upper right button on the screen. Repeat the open and exit steps until you are confident with the procedure.

1.7 Try to start a new drawing with another set up ‘use a wizard’ and ‘use a

template’

1.8 Using the Toolbars Dialog Box

• At the Command prompt enter toolbar. The toolbars dialog box is displayed, as shown in the figure 1.17

• In the Toolbars list box, check the modify 11 checkbox. The Modify 11 toolbar is displayed in the drawing windows as a floating toolbar

• Now you will change the Modify 11 toolbar from a floating toolbar to a docked toolbar. To do this, place the cursor on the title bar on the toolbar, then press and hold the left mouse button

• Drag the modify 11 toolbar to the docking region under the Object Properties toolbar, then release the left mouse button. When the toolbar is docked, the title bar name is no longer displayed.


• In the Toolbar dialog box, clear the Modify 11 Checkbox. The Modify 11 toolbar is no longer displayed.

• Choose Close to close the Toolbars dialog box.


FEEDBACK TO ACTIVITY 1b Once you have completed this activity, please refer to your

lecturer for further comments.


ANSWER ALL THE QUESTIONS BELOW QUESTION 1-1

a) How many ways can you start an AutoCAD drawing session? What are they?

b) How can you disable and reactivate the display of the Start Up dialog

box?

c) Describe the AutoCAD application window and explain each window area.

Toolbars

Layer Status Wi d

Command Line

Crosshair Cursor

Status Line

Menu Bar


d) How many way provided by AutoCAD to begin drawing. Explain.

e) What is the purpose of ‘Advanced Setup’ and list all the steps to draw by using ‘Advanced Setup’ format.


FEEDBACK TO SELF-ASSESSMENT

ANSWERS QUESTION 1-1

a) Two ways to start AutoCAD i. Click on icon AutoCAD R14 on the Desktop ii. Press Start>Programs>AutoCAD R14

b) We can activate using the following ways

Pull-down menu : File>New Toolbar :

We can disable by clicking cancel button at start up dialog box and upper right click at the start up dialog box.

c)

Menu Bar

Toolbars

Layer Status Window

Crosshair Cursor

Drawing Area

Status Line Command Line


Toolbars AutoCAD R14 provides a variety of toolbars. Each toolbar contains a number of icon buttons that can be selected to invoke command.

Menu Bars These menus provide an alternative method of accessing command and dialog boxes other than the Command Prompt or a toolbars button. They are termed pull-down menus because when you choose one with your left mouse button, the menu is displayed beneath its title, as if you were pulling the menu down from its title. Command Line The command line is a docked or floating window where you can enter names or command and where AutoCAD displays prompts and messages. Layer Status Window Layer status window shows the current layer setting. Status Line The status line is a set of informative words or symbols that gives the status of the drawing aids. The following drawing aids can be toggled on or off by double-clicking on the desired word or by using Function keys or Ctrl key sequences.

d) There are 4 ways to begin the drawing. They are: “ Use a Wizard ” - lead through setting up a drawing “ Use a Template ” - start a drawing based on the template

“ Start from Scratch ”- begin drawing quickly using default English or Metric settings

“ Open a Drawing ” - Open an existing drawing


e) ‘Advanced Setup.’

Choose the Advanced Setup wizard to set up the drawing area and change settings, such as text height and snap spacing, to an appropriate scale. You can also establish basic layout features.

Step 1 : Units Step 2 : Angles Step 3 : Angle Measure Step 4 : Angle Direction Step 5 : Area Step 6 : Title Block Step 7 : Layout

E 2004/2/1 Entering Command and Data Input

UNIT 2

ENTERING COMMAND AND

DATA INPUT

OBJECTIVES

General Objective : To understand and use the methods of entering command and data

input

Specific Objectives : At the end of the unit you will be able to :

Enter command by three different methods.

Create drawing by coordinate entry.

Use Direct Distance Input to create drawing.

Create a drawing by using Absolute Cartesian Coordinate.

Create a drawing by using Relative Coordinate.

Create a drawing by using Polar Input.

Explain the deferential four methods coordinate entry.


INPUT 2a

2.1 HOW TO BEGIN A COMMAND

There are three possible methods for entering commands in AutoCAD depending on

your preferences setting ( for the screen menu ). Generally any one of the three

methods can be used to invoke a particular command.

1. Keyboard Type the command name, command alias, or

accelerator ( Ctrl ) keys at the keyboard

2. Pull-Down Menu Select the command or dialog box from a pull-down

menu.

3. Toolbars Select the command or dialog box by PICKing an icon

( tool ) from a toolbar

2.1.1 Keyboard.

When you enter a command in a command window, AutoCAD either displays a

dialog box or prompts you for further information. This line of Command text is

termed the Command Prompt. The Command prompt asks you to specify coordinate

value, command options, or any other data needed to complete the command. The

following text is an example of the Command prompt for the PLINE command.


Figure 2.1 : Example of the Command prompt.

Once you are comfortable entering commands at the Command prompt, you can

learn the command aliases, which are basic one- or two- or three- letter abbreviations

of the commands. Many commands have an aliases, and learning these can help you

work faster and more productively. A list of all the command aliases is located in the

Help menu.

2.1.2 Pull Down Menu

When you perform a Typical installation of AutoCad, you are presented with a menu

bar containing 10 menus:

Figure 2.2 : Menu Bar with 10 menus.

These menus provide an alternate method of accessing command and dialog

boxes other than the command prompt or toolbar button. They are term pull down

menu because when you choose one with your left mouse button, the menu is

display beneath its title, as if you were pulling the menu down from its title. The

menu remains present until you click anyway outside of it.

2.1.3 Toolbars

Another method of performing commands is through the various toolbar

tools. There are many tools in the 21 toolbars, but those most frequently used,

relating to file, edit and view, are found in the Standard toolbar, shown in the

following figure:


Figure 2.3 : Standard Toolbars

To display other toolbars, you can access the Toolbar dialog box in the following

ways:

Toolbar : Right click any currently visible toolbar

Menu : View > Toolbars

Command : TOOLBAR

The Toolbars dialog box is displayed as shown in figure below:

Figure 2.4 : Toolbars dialog box

Clik on the box to choose any toolbars you need to use. Then, clik ‘Close’ button to end the

session.


ACTIVITY 2a

FILL IN THE BLANK.

2.1 List three methods for entering command in AutoCAD R14. Explain.

i.

ii.

iii.

2.2 Give the steps to access the ‘line’ command to draw a line by using the pull

down menu.

2.3 How can we display the ‘toolbar box?


Feedback To Activity 2a

ANSWERS.

2.1.




menu.



2.2. Pull Down Menu : Draw > Line

2.3. Toolbar : Right click any currently visible toolbar

Menu : View > Toolbars

Command : TOOLBAR


INPUT 2b

2.2 CREATING DRAWING BY USING COORDINATE ENTRY

AutoCAD provides various commands that you use to locate points in the drawing

plane. You can create a drawing by using Direct Distance entry, Absolute

Coordinates, Relative Coordinates, and Polar entry methods.

2.2.1 Direct Distance Entry.

To enter point you can use a feature called direct distance entry. With direct

distance entry, you can specify a relative coordinate by moving the cursor in the

desired direction and then entering a distance.

Coordinate value are specified by moving the cursor to indicate a direction

and then entering the distance from the first point. This is useful when you need to

quickly specify a length. An efficient way to create object constrained to the current

axes is to use direct distance entry combined with Ortho mode turned on.

Direct distance entry can used with all commands except those that prompt

you to enter real values. This commands include ARRAY, MEASURE, and

DIVIDE.

2.2.2 Absolute Cartesian Coordinate Input.

Absolute coordinate system can be used when you know the exact X and Y

values of the point you want to place in the drawing window. The absolute

coordinates method uses the Cartesian coordinate system to locate points in the

drawing window. All points are measure from origin (0,0).


The Cartesian coordinate system has three axes X, Y, and Z that are used to

locate points and create objects. The Cartesian coordinate system uses distances ( in

unit ) to locate points along intersecting axes, the horizontal ‘X’ axes and the vertical

‘Y’ axes. The intersection of these axes called the origin, where X = 0 and Y = 0

denoted as ( 0,0). These axes divide the coordinate system into four quadrant each

having positive, negative or positive and negative X and Y values.

You can draw a line by starting at the 0,0 and end at the point 3,4

Figure 2.5 : Two dimensional Cartesian coordinate system.

World Coordinate System ( WCS )

When start a new session, by default you enter the World Coordinate System (WCS).

This system consist of a horizontal X displacement, a vertical Y displacement, and a

Z displacement that is perpendicular to the XY plane. The Z displacement is used for

3D drawing. All X,Y and Z coordinate values are measured from the origin. The

origin is located at the intersection of X, and Y axes (0,0). The origin is originally

located in the lower left corner of a drawing. The WCS cannot be redefined, and all

other user coordinate system are based on the WCS.


User Coordinate System ( UCS )

The User Coordinate System ( UCS ) lets you establish your own coordinate

origin. The UCS is movable, meaning that the origin can be moved to any desired

orientation and its axes can be rotated. The UCS icon is displayed by default in the

lower left corner of the drawing window. The icon is used to help better

understanding the location and orientation of the movable UCS. The X and Y arrows

point in the positive direction of the axis. The W in the following figure indicates the

WCS is current. The UCS icon is shown in the following figure:

Figure 2.6 : UCS icon

Method for invoking the UCS command include:

Toolbar : Standard

Menu : Tools > UCS

Command : UCS

Relative Cartesian Coordinate Input.

A relative Cartesian coordinate is entered as the X and Y distance from the

last point you specified. Use relative X,Y coordinate when you know the position of

a point in relation to the previous point. For example, to locate a point at a relative

direction of 4,5 from the first point specified, precede the next coordinate with the @

symbol. The following example demonstrate how to enter a relative coordinate:


At the command prompt, enter line.

In response to the From point command prompt, enter 0,0

In response to the To point command prompt, enter @4,5.

Figure 2.7 : example to entering relative coordinate

Polar Input

A polar coordinate is entered as a relative distance and angle from an absolute

coordinate or the last point specified.

To enter a polar coordinate, enter a distance and an angle, separated by an

angle bracket (<). For example to specify a point that is at a distance of 2.5 units

from the previous point and an angle of 45 degree, enter @ 2.5 < 45.

By default, angles increase in the counterclockwise direction and decrease in

the clockwise direction. To move clockwise, enter a negative value for the angle. For

example, entering @3<-45 is the same as entering @3<315.


Figure 2.8 : Polar coordinate angles


ACTIVITY 2a

ANSWER ALL THE QUESTIONS BELOW.

2.4

figure 3.7

a) Refer to the figure 3.7, determine

1) the polar coordinate of Point “E” from Point “D”

2) the absolute coordinate of the center of circle “I”

3) the polar coordinate of Point “A” from Point “H”


b. Supply the appropriate absolute, relative and/or Polar coordinates for these

`figure in the matrix below each object.

5 4

3 6 72

15 1114

10

13 12

9 81/17 16


FEEDBACK TO ACTIVITY 2b

ANSWERS

2.4

a)

1. @4 < 90°

2. 6,10

3. @12 < 270° / @12 < -90°

b)

@ 0, 5.0 @5 <90 @ 2<0

0.5,5.02.5 , 5.0 @ 2.0, 02.5 , 7.0 @ 0, 2.0 @ 2 < 90

@ 7 < 0 9.5 , 7.0 @ 7.0 , 09.5 , 5.0 @ 0 , -2.0

@ 2.0 , 0@ 2 < 270 @ 2 < 0 11.5 , 5.0@ 5 < 270 11.5 , 0.5

10.0 , 0.5@ 0 , -5.0@ -1.5 , 0 @ 1.5 < 180

10.0 , 3.5 @ 0 , 3.5@ -3.3 , 0@ 0 , -1.0

@ 3.5 < 90 6.8 , 3.5

@ 1 < -90 @ 3.3 < 180

6.8 , 2.55.0 , 2.5 @ -1.5 , 0

@ 0 , 1.0@ 1.5 < 180 @ 1 < 90 5.0 , 3.5

@ -3.3 , 0 @ 3.3 < 180 2.0 , 0.50.5 , 0.5

2.0 , 3.5@ 0 , 3.5 @ 3.5 < 270 @ -1.5 , 0 @ 1.5 < 180


SELF- ASSESSMENT

ANSWER ALL THE QUESTIONS BELOW

QUESTION 2-1 a) List all the way to create the drawing by coordinate entry. b) Explain the methods to entering command.

QUESTION 2-2

a) Construct one-view drawings of the following figure using the LINE command along with coordinate or direct distance modes.


b) Complete the table below with Absolute and Relative Coordinate according to figure below.



ANSWERS. QUESTION 2-1.

a) CREATING DRAWING BY USING COORDINATE ENTRY

AutoCAD provides various commands that you use to locate points in the drawing

plane. You can create a drawing by using Direct Distance entry, Absolute

Coordinates, Relative Coordinates, and Polar entry methods.

b) There are three possible methods for entering commands in AutoCAD depending on

your preferences setting ( for the screen menu ). Generally any one of the three

methods can be used to invoke a particular command.




menu.




2-2

b)

3.65 , 3.25

@ 2.5 , 0

5.5 , 3.0@ -1 , -1

2.0 , 2.0

@ 0 , -14.5 , 0

3.65 , 3.25

@ 0 , 0.5 @ 2.0 , 0@ 1 , -0.5

4.5 , 4.55.5 , 4.0

2.5 , 4.50@ 0.5 , 02.5 , 3.75@ 0 , 1.752.0 , 3.75

E2004/3/1 DRAWING AIDS , DRAWING LIMITS & DISPLAY CONTROL

DRAWING AIDS, DRAWING LIMITS AND DISPLAY CONTROL

UNIT 3

OBJECTIVES

General Objective :To understand and apply the concept of drawing aids, drawing

limits and display control


Specify the Snap and Grid increment.

Use the Setup and Create New Drawing dialog boxes

to accomplish basic drawing setup.

Use the various OSNAP command options.

Use the various ZOOM command options.

Adjust the display using Realtime ZOOM and PAN

modes.

Use the Ariel View feature to Zoom and Pan different

parts of a drawing.

Create and restore views with the View Control dialog

box.

Use and distinguish the REDRAW, REGEN, and

REDRAWALL commands.


INPUT 3a

DRAWING AIDS

3.0 INTRODUCTION

When placing a line, arc or circle in a drawing, the easiest method is to enter point by selecting a point in the drawing windows. The problem with these methods is that it is inaccurate. To assist you in selecting points in the drawing windows, you can setup the drawing aids to suit the design requirements of your current project. AutoCAD provides with a number of features that will increase your efficiency and make more productive. Many of these features are contained in the Drawing Aids dialog box. They include Snap, Grid and Ortho as shown in the Figure 3.1

Figure 3.1 : Drawing Aids Dialog Box

Methods for opening the Drawing Aids dialog box include: Menu : Tools> Drawing Aids Command : DDRMODES


The Ortho option is used to turn Ortho mode ON or OFF. By selecting Ortho command, we

can draw a line weather horizontal or vertically.

The Solid Fill mode option controls whether objects such as Polylines with widths and

Solids are displayed filled or in outline. This mode can be controlled from the command line

using the FILL command.

When Quick Text is checked, all text objects in the drawing will be displayed with empty

boundary boxes. This option is often used to increase Regen and Redraw times when the

drawing has a lot of text. This mode can also be set using the QTEXT command.

The Blips option controls whether temporary blips will be displayed when points are picked

or entered. Blips can be removed from the display using the Redraw command but they can

only be suppressed completely by turning Blip mode OFF. This mode can also be set using

the BLIPMODE system variable.

Highlight mode determines whether objects are highlighted or not when they are selected.

You can also control highlighting using the HIGHLIGHT system variable.

The Groups option turns automatic Group selection ON and OFF. When Groups mode is

turned ON, selecting an object which is a member of a previously defined group will

automatically select the whole group.

The Hatch option determines whether the hatch boundary is selected when a hatch object is

selected or not. When this mode is turned ON, the boundary is automatically selected with

the hatch.

3.1 SNAP

SNAP, when activated by pressing F9 or double-clicking on SNAP in the status line (

Figure 3.2 ) forces the cursor position to regular increments. The function can be assistance

to you by making it faster and more accurate for creating and editing objects. The default

snap setting is 0.5 The Snap command is used to set the value for these invisible snap

increments. Snap spacing can be set to any value.


Figure 3.2 : The Status Line

The Snap command is easily typed, displaying the options in command line format. The

command line format is as follows:

Command : Snap

Snap spacing or ON/OFF/Aspect/rotate/Style< current value ): ( value or

letter ) ( enter a value or option )

ON/OFF

Selecting ON or OFF accomplishes the same action as toggling the F9 key, pressing

Ctrl+B, or double clicking SNAP on the status line. Typically, SNAP should be ON for

drawing and editing but turned OFF to make object selection easier ( the cursor moves

smoothly to any location with SNAP OFF )

Aspect

The Aspect option allows specification of unequal X and Y spacing for SNAP. This action

can also be accomplished in the drawing Aids dialog box by entering different values for X

Spacing and Y Spacing.

Rotate

SNAP can also be rotated about any point and set to any angle. When SNAP has been

rotated, the GRID, ORTHO, and “crosshairs” automatically follow this alignment.

Style

The style option allows switching between a standard snap pattern ( the default square or

rectangular ) and an Isometric snap pattern. If using the dialog box, toggle Isometric

Snap/Grid On. When the SNAP Style or Rotate angle is changed, the GRID automatically

aligns with it.


3.2 GRID

GRID is visible on the screen, whereas SNAP is invisible. GRID is only a visible display of

some regular interval. GRID and SNAP can be independent of each other. In other words,

each can have separate spacing settings and the active state of each (ON, OFF) can be

controlled independently. The GRID follows the SNAP if SNAP is rotated or changed to

Isometric Style. Although the GRID spacing can be difference than SNAP, it can also be

forced to follow SNAP by using snap option. The default GRID setting is 0.5.

Figure 3.3 : The GRID is ON in the drawing area

The GRID cannot be plotted. It is not comprised of point object and therefore is not part of

the current drawing. GRID is only visual aids.

Grid can be accessed by command line format ( shown below ) or set via the Drawing Aids

dialog box ( Figure 3.2 ).

Command : grid

Gridspacing ( X ) or ON/OFF/Snap/Aspect<current value>: (value or letter)

( enter a value or option )

Grid spacing ( X )

If you supply a value for the grid spacing, GRID is displayed at the spacing regardless of

SNAP spacing. If you key in an X as a suffix to the value ( for example, 2X ), the GRID is

displayed as that value times the SNAP spacing ( for example, “2 times” SNAP )


ON/OFF

The ON and OFF options simply make the grid visible or not ( like toggling the F7 key,

pressing Ctrl+G or double clicking GRID on the status line.

Snap

The snap option of the grid command forces the GRID spacing to equal that of SNAP, even

if SNAP is subsequently changed.

Aspect

The aspect option of Grid allows difference X and Y spacing ( causing a rectangular rather

than a square GRID )

3.3 THE FUNCTION KEYS

Many of the modes described above can be controlled quickly using the keyboard function

keys. In most cases this is quicker than using a pull-down or the command line. The

function keys are arranged along the top of your keyboard. AutoCAD uses function keys F1

to F10. Their use is described below.

The F1 key on your keyboard brings up the "Help Topics: AutoCAD Help" dialogue box.

You can use this dialogue box to search for help on any AutoCAD command or topic.

Simply follow the instructions in the dialogue box and when you have found the item you

wish to view, click on the "Display" button. You will usually be given a list of options in the

"Topics Found" dialogue box, select the most appropriate and click the "Display" button to

see the item.


Figure 3.4: Help Topic Box

The F2 key is used to toggle (turn ON and OFF) the AutoCAD text window. This is a

floating version of the command window which can be resized to suit your requirements.

The text window contains the whole command history from the beginning of the drawing

session. If you wish, you can scroll back to see which commands you have used. The text

window is also useful for viewing the results of commands like ‘LIST’ which report to the

command line on a number of lines which may scroll off the command window and make

them difficult to view.

Figure 3.5: AutoCAD Text Windows

The F3 key displays the "Osnap Settings" dialogue box.

The F4 key on your keyboard toggles tablet mode ON and OFF. This only has an effect if a

digitizing tablet has been calibrated.


The F5 key cycles through the Isoplanes, this only has an effect if "Isometric Snap/Grid"

mode is ON. The options are Left, Top and Right. The different options describe the plane

in which Ortho mode works. It also affects the orientation of Isocircles drawn with the

Ellipse command. The illustration on Figure 3.6 shows a cube with ‘isocircles’ drawn on the

top, left and right faces. Each isocircle was drawn using the corresponding isoplane.

Figure 3.6

The F6 key is a three way toggle which changes the co-ordinate reading in the status bar. By

default the status bar shows co-ordinates using the Cartesian system. You can use the F6 key

to turn the co-ordinate readout OFF and to change to the polar system when you are in pick

mode.

The F7 key is used to toggle grid mode ON and OFF. When grid mode is ON a grid of dots

is shown on the screen as a drawing aid. You can set the grid spacing by using "Drawing

Aids" from the "Tools" pull-down. The grid points do not necessarily reflect the Snap

setting, they can be set independently, and however, you can force the grid to reflect the

snap setting by giving the grid setting a value of zero. The word "GRID" is highlighted in

the status bar when grid is set ON.


The F8 key on your keyboard can be used to toggle Ortho (orthogonal) mode ON and OFF.

When Ortho mode is ON AutoCAD will only allow you to draw either vertical or horizontal

lines. You can think of it as being a computer version of the parallel motion on your

drawing board. You can see if Ortho mode is ON by looking at the status bar. The word

"ORTHO" is highlighted when Ortho is turned ON.

The F9 key can be used to toggle Snap mode ON and OFF. Snap makes the crosshairs jump

to points on a defined grid. The snap spacing can be set using the "Drawing Aids" dialogue

box from the "Tools" pull-down menu. You can also see if Snap mode is ON by looking at

the status bar.

The F10 key is used to control the display of the status bar, the display can be toggled OFF

and ON.

3.4 OBJECT SNAP

The Object Snaps (Osnaps for short) are drawing aids which are used in conjunction with

other commands to help you draw accurately. Osnaps allow you to snap onto a specific

object location when you are picking a point. For example, using Osnaps you can accurately

pick the end point of a line or the center of a circle. Osnaps in AutoCAD are so important

that you cannot draw accurately without them. For this reason, you must develop a good

understanding of what the Osnaps are and how they work.

This simple example is to give you an idea how Osnaps work. Follow the command

sequence below to draw a circle and then to draw a line from the center point of the circle to

a point on the circle's circumference at the 12 o'clock position.

To Draw the Circle

Command: CIRCLE

3P/2P/TTR/<Center point>:

(pick a point in the middle of the drawing window)

Diameter/<Radius>:

(pick another point to draw the circle, the size is not important)

Figure 3.7


To Draw the Line using Osnaps

Command: LINE

From point: CEN (this is the short-cut for the Center Osnap)

_cen of (pick a point on the circumference of the circle, P1 in the illustration)

To point: QUA (this is the short-cut for the Quadrant Osnap)

_qua of (pick a point on the circumference of the circle, P2 in the illustration)

To point: (to end)

When you use Osnaps you need only pick a point which is near to the point required

because AutoCAD automatically snaps to the object location implied by the particular

Osnap you use. Notice that when you move the cursor close enough to an Osnap location, it

is highlighted with an Osnap marker. Each Osnap has a different marker. As you have

already seen, the Center Osnap marker is a circle and the Quadrant Osnap marker is a

diamond. Notice also that when you move the cursor over a snap point the cursor jumps to

the snap location. This feature is known as Magnet.

One thing that often catches new users out is that when you want to snap to the centre of a

circle, the pick point should be on the circle's circumference. This is because the circle has

no solidity, it is only an outline.

Although you can get quite close to the result above by picking freehand you will never be

able to pick as accurately as you can using Osnaps. Many AutoCAD

commands rely upon the fact that objects have been drawn accurately

and so you should always use Osnaps when you need to pick a point at a

particular location.

There are four basic methods of accessing the Osnaps:

• The Osnaps are available from a flyout button on the Standard

toolbar, see illustration on Figure 3.8

Figure 3.8


• The Osnaps are also available on their own Object Snap toolbar. If this toolbar is not

already displayed, you can display it using the TOOLBAR command, View

Toolbars… from the pull-down menu. When the Toolbar dialogue box appears,

simply check the box next to "Object Snap" in the toolbars list. Many AutoCAD

users work with the Object Snap toolbar permanently docked on their screen because

it gives one-click access to all of the Osnaps, making drawing much more efficient.

• You can also access the Osnaps from the cursor menu. Hold the Shift key down on

the keyboard and right-click the mouse to bring up the cursor menu. The menu

appears at the current cursor position.

• Finally, you can also access the Osnaps from the keyboard by typing their

abbreviated name.

There are eleven Osnaps in all and although they are all useful in certain situations you will

probably find yourself using about half of them on a regular basis and the other half in

special circumstances. However, it's a good idea to get to know all of the Osnaps so that you

can plan your drawing, knowing all of the tools at your disposal. A sensible use of Osnaps is

the best way to improve your drawing efficiency.

Each of the sections below is accompanied by a small screen-shot illustrating the Osnap in

use. In each case, drawing objects are shown in pale blue (cyan), the Osnap marker is shown

in red and the cursor cross-hairs in white. The corresponding Snap Tip is also shown. Snap

tips appear if you let the cursor hover over an Osnap location for a second or so and have a

similar function to the toolbar Tool Tips.

Endpoint

Toolbar :

Pull-down : Shift + Right Click Endpoint

Keyboard : END (when selecting objects)


The Endpoint Osnap snaps to the end points of lines and arcs and to polyline vertices. This

is one of the most useful and commonly used Osnaps.

Midpoint

Toolbar :

Pull-down : Shift + Right Click Midpoint

Keyboard : MID (when picking)

The Midpoint Osnap snaps to the mid poins of lines and arcs and to the mid point of

polyline segments.

Intersection

Toolbar :

Pull-down : Shift + Right Click Intersection

Keyboard : INT (when picking)

The Intersection Osnap snaps to the physical intersection of any two drawing objects (i.e.

where lines, arcs or circles etc. cross each other) and to Polyline vertices. However, this

osnap can also be used to snap to intersection points which do not physically exist. This

feature is called the Extended Intersection (see the illustration above). To use the apparent

intersection feature, you must pick two points to indicate which two objects should be used.

Apparent Intersect

Toolbar :

Pull-down : Shift + Right Click Apparent Intersect

Keyboard : APP or APPINT (when picking)

Apparent Intersection snaps to the point where objects appear to intersect in the current

view. For example, you may be looking at a drawing in plan view where two line cross, as


in the illustration. However, since AutoCAD is a 3 dimensional drawing environment, the

two lines may not physically intersect. One line may be at ground level and the other may be

10 meters or more above or below ground level. As with the Intersection Osnap, Apparent

Intersection also has an "Extended" mode.

Center

Toolbar :

Pull-down : Shift + Right Click Center

Keyboard : CEN (when picking)

The Center Osnap snaps to the centre of a circle, however, the pick point used to pick the

centre must be on the circumference of the circle. This often causes some confusion for new

users.

Quadrant

Toolbar :

Pull-down : Shift + Right Click Quadrant

Keyboard : QUA or QUAD (when picking)

The Quadrant Osnap snaps to one of the four circle quadrant points located at north, south,

east and west or 90, 270, 0 and 180 degrees respectively.

Tangent

Toolbar :

Pull-down : Shift + Right Click Tangent

Keyboard : TAN (when picking)


The Tangent Osnap snaps to a tangent point on a circle. This osnap works in two ways. You

can either draw a line from a point to the tangent point (see illustration) or you can draw a

line from a tangent point, the latter is reffered to as the "Deffered Tangent" snap mode.

Perpendicular

Toolbar :

Pull-down : Shift + Right Click Perpendicular

Keyboard : PER or PERP (when picking)

The Perpendicular Osnap snaps to a point which forms a perpendicular with the selected

object. As with the Tangent Osnap, Perpendicular can be used to draw a line to a

perpendicular point, as in the illustration or from a perpendicular point, known as the

"Deffered Perpendicular" snap mode

Insert

Toolbar :

Pull-down : Shift + Right Click Insert

Keyboard : INS (when picking)

The Insert Osnap snaps to the insertion point of a block, text or an image.

Node

Toolbar :

Pull-down : Shift + Right Click Node

Keyboard : NODE (when picking)

The Node Osnap snaps to the center of a Point object. This osnap can be useful if you have

created a number of Points with the ‘Measure’ or ‘Divide’ commands. You could, for

example insert a number of regularly spaced tree symbols (blocks) along a line by using the

Node Osnap for the insertion point of each block.


Figure 3.9

The image above shows a Spline (cyan). The Measure command has been used to set Points

(red) at regular intervals and a tree symbol has been inserted with the Insert command at

each Point location using the Node Osnap.

Nearest

Toolbar :

Pull-down : Shift + Right Click Nearest

Keyboard : NEA or NEAR (when picking)

The Nearest Osnap snaps to the nearest point on a drawing object. This Osnap is useful if

you want to make sure that a pick point lies on a drawing object but you don't necessarily

mind exactly where it is located.

From

The From Object Snap is a little more complicated than the other object snaps but it is well

worth getting to know because it can be very useful.

Toolbars :

Pull Down : Shift + Right Click From

Keyboard : FROM ( When Picking )


The From Osnap can be used in conjunction with other osnaps or ordinary pick points and

relative co-ordinates to pick offset points. The From Osnap does not snap to object snap

locations, rather it can be used to snap to points at some distance or offset from an object

snap location. Consider the following example.

Look at the illustration on the right. It shows a circle drawn on top of a line. It is

quite difficult to see how this circle could have been drawn accurately without the use of

construction lines. However, the From Osnap can be used to draw the circle without any

construction lines. Follow the command sequence below to discover how this is done.

To draw the Line

Command: LINE

From point: (pick a point in the lower half of the screen)

To point: @0,30

(this is a relative co-ordinate, 30 units above the first point)

To point: (to end)

To draw the Circle

Command: CIRCLE

3P/2P/TTR/<Center point>: FROM

_from Base point: END ( click at the top of line )

_endp of <Offset>: @0,10

(this co-ordinate is a point 10 units from the endpoint in the Y direction)Diameter/<Radius>

<10.0000>: 10

(a radius value of 10 ensures that the southern point on the circle will just touch the top of

the line)

Your drawing should now look like the illustration above. Practice using the From Osnap

until you are quite sure how it works. Don't forget to prefix all co-ordinates with the @

symbol to let AutoCAD know that you are entering a relative co-ordinate. The North Point

exercise below demonstrates more uses of the From Osnap.


3.5 DRAWING LIMITS

The limits command allows you to set the size of the drawing area by specifying the lower

left and upper right corners in X,Y coordinates values. Methods for invoking the limits

command include :

Pull-down menu : Format>Drawing Limits

Command : Limits

When using command line, we can get the following step

Command : limits

Reset Model space limits

ON/OFF/<Lower left corner><0,0 or current values>: x,y or Enter ( Enter an X,Y

value or accept the 0,0 default-normally use 0,0 as lower left corner. )

Upper right corner < 19,9>:x,y ( Enter new values to change upper-right corner to

allow adequate drawing area.)

The default Limits values in AutoCAD are 12 and 9; that is, 12 units in the X direction and

9 unit in the Y direction ( figure 3.10 ). Starting a drawing by any of the following methods

( of the setup or create new Drawing dialog boxes ) results in limits of 12 X 9

Figure 3.10


If the GRID is turned ON, the dots are displayed only over the Limits. The AutoCAD screen

( default configuration ) displays additional area on the right past the Limits the units are

generic decimal units that can be used to represent inches, feet, millimeters, miles, or

whatever is appropriate for the intended drawing. Typically, however, decimal units are

used to represent inches or millimeters. If the default units are used to represent inches, the

default drawing size would be 12 by 9 inches.

Remember that when a CAD system is used to create a drawing, the geometry should be

drawn full size by specifying dimensions of object in real world units. A completed CAD

drawing or model is virtually an exact dimensional replica of the actual object. Scaling of

the drawing occurs only when plotting or printing the file to an actual fixed-size sheet of

paper.

Before beginning to create an AutoCAD drawing, determine the size of the drawing area

needed for the intended geometry. After setting Units, appropriate Limits should be set in

order to draw the object or geometry to the real-world size in the actual units. There are no

practical maximum or minimum settings for Limits.

The X,Y values you enter as Limits are understood by AutoCAD as values in the units

specified by the Units command. For example, if you previously specified Architectural

units, then the values entered are understood as inches unless the notation for feet ( ` ) is

given ( 240,180 or 20’,15’ would define the same coordinate). Remember, you can type in

explicit feet and inch values only if Architectural or Engineering units have been specified

as the drawing units

If the ON option of Limits is used, limits checking is activated. Limits checking prevents

you from drawing objects outside of the limits by issuing an outside-limits error. This is

similar to drawing “ off the paper.” Limits checking is OFF by default.


Limits also defines the display area for GRID as well as the minimum area displayed when

Zoom All is used. Zoom All forces the full display of the limits. Zoom All can be invoked

by typing Z ( command alias ) then A for the all option

Changing Limits does not automatically change the display. As a general rule, you should

make a habit of invoking a Zoom All immediately following a change in Limits to display

the area defined by the new limits ( Figure 3.11 )

Figure 3.11


ACTIVITY 3a


3.1 What is the function of Snap and Grid?. How to adjust the Snap 1.5 (X and

Y) spacing and Grid to 2.0 ( X and Y) spacing?

3.2 Complete the steps for the drawing setup below:

Begin a New Drawing. When the Start Up or Create New Drawing dialog

box appears, select Start from Scratch. Select the English default settings.

Set the GRID to 1.

Set SNAP to 0.125

Save this drawing.

3.3 Give the method for accessing the Osnaps and list all the Osnaps.



ANSWERS 3.1 The function of Snap and Grid is making faster and accurate for creating and editing

object. It also functions as a guidance for creating objects. We can adjust the Snap and Grid by using ‘Drawing Aids Dialog Box’ and set the X

to 1.5 and Y to 2.0 or by type snap / grid and then set the X and Y.

3.4 There are four basic methods of accessing the Osnaps:

• From flyout button on the Standard toolbar

• From TOOLBAR command, View Toolbars… from the pull-down menu.

• From the cursor menu. Hold the Shift key down on the keyboard and right-click the mouse to bring up the cursor menu. The menu appears at the current cursor position.

• From the keyboard by typing their abbreviated name.

Osnaps List 1. Endpoint 2. Midpoint 3. Intersection 4. Apparent Intersect 5. Center 6. Quadrant 7. Tangent 8. Perpendicular 9. Insert 10. Node 11. Nearest


3.6 DISPLAY CONTROL

The accepted CAD practice is to draw full size using actual units. Since the drawing

is a virtual dimensional replica of the actual object, a drawing could represent a vast

area (several hundred feet or even miles) or a small area (only millimeters). The

drawing is created full size with the actual units, but it can be displayed at any size

on the screen. Consider also that CAD systems provide for a very high degree of

dimensional precision, which permits the generation of drawings with great detail

and accuracy.

Display commands provide you with different options for changing the view

of your drawing while it is being created. These commands make it easier to work

with your drawing, and see the overall effects of changes. the commands that

facilitate viewing different areas of a drawing are ZOOM, PAN, and View.

When you use drawing or editing commands, you can utilize the transparent

PAN command and ZOOM command options to change the view and magnification

of a drawing. You can also use display commands for saving and restoring specific

views, or to display several views.

The Viewing commands are found in the View pull-down menu (Figure 3.12 ).

INPUT 3b


The Standard toolbar contains a group of tools (icon buttons) for the Figure 3.12

Viewing commands located near the right end of the toolbar ( Figure. 3.12 ). The

Realtime options of Pan and Zoom, Zoom Previous, and Aerial View each has an

icon permanently displayed on the toolbar, whereas the other Zoom options are

located on flyouts.

Figure 3.12: View pull-down menu

Figure 3.13: Standard toolbar button for viewing

Aerial View

Pan Realtime

Zoom Realtime

Zoom Previous


3.7 USING ZOOM COMMAND

When you create a drawing, you may need to change the way objects are viewed in

the drawing window. To achieve this, the orientation, magnification, or position of

the drawing may have to be adjusted. The ZOOM command options let you change

the view by increasing or decreasing the size of displayed images. You zoom in to

magnify objects so you can see more details. You zoom out to reduce objects in the

drawing window and view a larger portion of the drawing.

Zooming does not change the true size of a drawing or object. It only changes the

size of the view in your drawing window. You can view the entire drawing, specify a

display window, or zoom to re a specific scale. We can get Zoom All Toolbar from

Flyout toolbar.

3.7.1 Zoom Window

The Zoom Window option lets you zoom in on an area of your drawing by using a

window to specify the viewing boundaries. When you enter the Zoom Window

option, AutoCAD displays a rectangular window in the drawing window. Select a

point to specify where you want your view to start, then move the window to cover

the area or section you want to magnify ( Figure 3.14 )

Figure 3.14: Using Zoom Window

Before After

START

END


Methods for invoking the zoom window option include:

Toolbar :

Pull Down Menu : View> Zoom > Window

Command : ZOOM> Window

3.7.2 Zoom Previous

The Zoom Previous option displays the last view of your drawing. This option lets

you restore as many as ten previous views.

Methods for invoking the Zoom Previous option include:

Toolbar:

Menu: View> Zoom> Previous

Command: ZOOM> Previous

3.7.3 Zoom All

The Zoom All option lets you view the entire drawing in the current viewport. The

display shows the drawing limits and all objects even if the objects extend outside of

the drawing limits.

Methods for invoking the Zoom All option include:

Toolbar :

Menu : View> Zoom > All

Command : ZOOM> All


3.7.4 Zoom Extents

The Zoom Extents option displays the region of the drawing where all objects you

draw are located. The display is based just on drawing objects, the drawing limits are

not considered to recalculate the display.

Methods for invoking the Zoom Extents option include:

Toolbar :

Menu : View > Zoom> Extents

Command : ZOOM> Extents

3.7.5 Zoom Center

The Zoom Center option lets you change the displayed size of an object and locate it

in the center of the viewport. When you enter the Zoom Center option, you are

prompted to locate a center point on the drawing plane. The next command prompt

lets you enter a magnification value or a height. The magnification value is followed

by an x which is the relative magnification factor. For the Height option, enter

smaller numbers for the height to enlarge the image size, and enter larger numbers

for the height to decrease the size.

Methods for invoking the Zoom Center option include:

Toolbar:

Menu: View > Zoom > Center

Command: ZOOM> Center

3.7.6 Dynamic

The Zoom Dynamic option uses a viewbox to adjust the display. The view box

represents your viewport. This means that the region of your drawing that you select


with the view box will be displayed in the entire drawing window. You can enlarge,

reduce, and move the viewbox around your drawing to select the desired view.

Methods for invoking the Zoom Dynamic option include:

Toolbar :

Menu : View > Zoom> Dynamic

Command : ZOOM> Dynamic

3.7.7 Zoom Scale

The Zoom Scale option uses a scale factor to adjust the display. The value you enter

should correspond to the limits of the drawing.

The Scale (X) option requires you to use positive numbers to change the

magnification factor. When you enter the X option, the current display can be

enlarged or reduced by a certain multiple. For example, entering 2 at the Zoom Scale

Command prompt will display your drawing at twice its size, relative to its full view.

However, entering 2x at the Zoom Scale Command prompt will display your

drawing at twice the size as displayed in the current view.

You use the Scale (XP) option for scaling the display in floating viewports created in

paper space. This is useful when you are plotting layouts of scaled multiview

drawings.

Methods for invoking the Zoom Scale option include:

Toolbar :

Menu : View> Zoom> Scale

Command : ZOOM> Scale


3.8 REALTIME DISPLAY

3.8.1 Zoom Realtime

When working with complex drawings, you spend significant time using the ZOOM

and PAN commands. After you invoke the command, the Realtime Zoom cursor is

displayed, drag the cursor down to decrease or up to increase the image. To activate

the Realtime ZOOM / PAN menu right-click the mouse.

The ZOOM/PAN cursor menu options include:

Exit - cancels the Realtime option and returns you to the Command prompt

Pan - Switches from Realtime ZOOM to PAN

Zoom - Switches from PAN to Realtime ZOOM

Zoom window - Displays a specified window and returns to REALTIME ZOOM

Zoom Previous - Restores the previous view and returns to the Realtime option

Zoom Extents - Displays the drawing extents and returns to the Realtime option

Methods for invoking the Realtime ZOOM command include:

Toolbar :

Menu : View> Zoom> Realtime

Commands : ZOOM

The Zoom/Pan Cursor menu is shown in the following figure:

Figure 3.15: The ZOOM/PAN Cursor Menu


3.8.2 PAN REALTIME

With the PAN command, you can move the drawing around the drawing window

without changing the magnification. The two options that let you change the display

are Realtime and Point.

Methods for invoking the PAN command include:

Toolbar :

Menu : View> Pan> Realtime

Command : PAN

When you select the Realtime PAN option, the cursor changes into a hand cursor. To

change the location of your drawing, press the left mouse button. This locks the

cursor into its current location relative to the coordinate system used in the current

viewport. As you move the mouse, the drawing image pans to a new location. The

view of the objects in the drawing window shift in the same direction as the cursor.

The PAN Point option lets you specify a single point. AutoCAD then uses the

selected point and the current view orientation to displace the image. You also can

specify two points, AutoCAD computes the displacement between the two points

then moves the image in the drawing window. You can also pan by entering absolute

or relative coordinates at the Displacement prompt. To invoke the Pan Point option,

select Pan from the View menu, then choose Point.

The PAN command also has preset options that move the drawing in the specified

direction. You can access these options from the View menu. They include Left,

Right, Up, and Down. A view of the Pan cascading menu is shown in the following

figure:


Figure 3.16: Pan cascading menu options

3.9 The Aerial View Zoom Feature

The Aerial View feature is a viewing aid that saves drawing time by displaying your entire

drawing in a separate window. You can then use the ZOOM and PAN command options

within the window to change the view of your drawing on the drawing window. If you keep

the Aerial View window open while you work, you can pan and zoom around your drawing

without entering commands at the Command prompt, or accessing them from the View

menu.

Methods for invoking the Aerial View window include:

Toolbar : Standard

Menu : View> Aerial View

Command : DSVIEWER

Figure 3.17: Realtime Pan and Zoom cursor menu


When you enter the Aerial View window, AutoCAD displays the Aerial View window by

default, in the same location and with the same size as it was located in the last drawing

session. This means that you may have to move or change the size of the Aerial View

window so that you can have a better view of the display window. To do so, use the left

mouse button to select the title bar. Drag the window to a desired location and release the

left mouse button. To change the size of the window, move your cursor to one of the four

corners. When you see the doubled-pointed arrow, drag the cursor to change the window

size.

The Aerial View window contains the following four menus labeled View, Mode, Options,

and Help.

The View menu lets you select three zoom options to change the magnification of the Aerial

View. These include Zoom In, Zoom Out, and Global.

Zoom In - Increases the magnification of the drawing in the Aerial View by

zooming in by a factor of 2, centered on the current view box.

Zoom Out - Decreases the magnification of the drawing in the Aerial View by

zooming out by a factor of 2, centered on the current view box.

Global - Displays the entire drawing and the current view in the Aerial View

window.

3.10 USING REDRAW, REGEN AND REGEN ALL

3.10.1 REDRAW

The REDRAW command quickly refreshes the display of the current viewport by

removing all blips and any marks left from the use of editing commands. Blips are

small crosses left on the drawing window after a point is selected. REDRAW is also a

transparent command.


Methods for invoking the REDRAW command include:

Menu : View > Redraw

Command : REDRAW

3.10.2 REGEN and REGENALL

The REGEN command refreshes the drawing window and recalculates all of the

objects in the drawing. When using the REGEN command, it will take AutoCAD a

longer time to redisplay your drawing than if the REDRAW command was used. This

is a major consideration when working with large drawings. The REGEN command

re-indexes the drawing database, re-computes drawing window coordinates for all

objects, and smoothes out all circles, arcs. ellipses, and splines. You may need to use

REGEN after changes in text styles, layer and linetype properties, and other changes

to properties.

Methods for invoking the REGEN command include:

Menu : View > Regen

Command : REGEN

The REGEN command only affects the current viewport. If you are working with

multiple viewports that need to be updated, use the REGENAL, command. The

REGENALL, command works the same way as REGEN except it regenerates all

viewports, and recalculates the drawing window coordinates and view resolution for

all objects in each of the active viewports.

Methods for invoking the REGENALL command include:

Menu :View > Regen All

Command : REGENALL


Example using REGEN ALL

Create the circle with diameter 10mm ( Start new drawing with metric setting ).

Then zoom the circle. The figure below shown that the circle before zoom, after

zoom and after using regen command

Figure 3.18 Using Regen All to smoother the display of object

Original Drawing After Zoom Windows After Regen All


ACTIVITY 3 b

EXERCISES.

3.5 Controlling the Display

You often use the ZOOM command options to change the view in the drawing

window. In this activity, you use the ZOOM options to display new drawing views.

A. Using the Zoom Command

1. Open the file C:\Program files\AutoCAD R14\Sample\campus.dwg. The drawing

looks like the following figure:

Figure 3.19 : Campus.dwg

A

B

2. From the View menu, choose Zoom, then choose Window.

3. In response to the First corner: prompt, select A. For the Other corner: select B.


The following figure shows the result of using zoom window:

Figure 3.20: Result of using ZOOM Window

4. To recall a previous display, you can use the Zoom command option Previous. At

the Command prompt, enter the command alias z.

5. Enter p at the Command prompt. The previous display is now displayed again.

6. To display all visible objects in the whole drawing, you can use the Zoom Extents

option.

7. From the View menu, choose Zoom, then choose Extents. All visible objects in the

drawings are now displayed.

8. To center an object in the middle of the drawing window, use the Zoom Center

option. At the Command prompt, enter z. Then enter c for the center option.


B. Using Realtime ZOOM and PAN

1. The REALTIME PAN and ZOOM commands let you quickly obtain the display you

want. Open Campus.dwg file and use REALTIME ZOOM

2. To use the REALTIME ZOOM command, enter z and accept the default command

option <realtime> by pressing ENTER.

3. The Realtime Zoom cursor is now displayed as a magnifying glass with plus and

minus signs. Press the left mouse and drag the Realtime Zoom cursor up and down

the drawing window. When the desired view is displayed in the drawing window,

release the left mouse button.

4. Press the right mouse button. The Pan/Zoom cursor menu is displayed. Select the

Pan option, as shown in the following figure:

Figure 3.21: Realtime Pan and Zoom cursor menu

5. The Realtime Pan cursor is now displayed as a hand in the drawing window. Position

the Realtime Pan cursor over the office building. Drag the cursor around the drawing

window, and when the desired view is displayed in the drawing window, release the

left mouse button and press ENTER.

6. This concludes the ZOOM Command exercise. You are encouraged to explore the

other Zoom command options and command entry methods.

7. Try another ZOOM command ( All, Extents, Center, Dynamics, Scale )


C. Using REDRAW, REGEN and REGEN ALL

Start New drawing. Start From Stractch > Metric. Create a circle with diameter 5

mm. Then zoom the circle using ZOOM Windows commands. What happen with this

circle? Using Regen All to make the circle smoothes

.



Please discuss with your lecturer


FOLLOW THE ENTIRE STEP BELOW AND ANSWER THE QUESTION.

QUESTION 3-1

a) Begin a New drawing. When the Start Up or Create New Drawing dialog box

appears, select Start From Scratch. Select the English default settings. Set Limits in

order to draw full size. Make the lower-left corner 0,0 and the upper-right at 24,18.

Set the grid to 1 and snap to 1. Draw the T character as shown below. Save your

drawing.

Figure 3.22

Then, set the Grid to 0.5 What happened with the grid and snap? Discuss with your lecturer.


b) Draw the marker of each Osnap below

Osnap Marker

i. Endpoint

ii. Midpoint

iii. Center

iv. Quadrant

v. Intersection

vi. Perpendicular

vii. Tangent

c) Follow this exercise to demonstrate the use of some of the most commonly used

Osnaps.

To Draw the Triangle

Command: LINE

From point: (pick a point in the middle of the drawing area)

To point: @15,0

To point: FROM

_from Base point: MID

_mid of : (pick a point near the middle of the line)

<Offset>: @0,75

To point: C (to close)

To Draw the Vertical Line

Command: LINE

Figure 3.24


From point: MID

_mid of : (pick point near the middle of the triangle base)

To point: @0,-100

To point:

To Draw the Horizontal Line

Command: LINE

From point: FROM

_from Base point: MID

_mid of : (pick a point near the middle of the vertical line)

<Offset>: @-25,0

To point: @50,0

To point:

To Draw the Circle

Command: CIRCLE

3P/2P/TTR/<Center point>: INT

_int of :(pick a point near the intersection of the two lines)

Diameter/<Radius> <12.5000>: 12.5

To Trim the Lines within the Circle

Command: TRIM

Select cutting edges: (Projmode = UCS, Edgemode = No extend)

Select objects: (pick the circle on its circumference)

Select objects:

<Select object to trim>/Project/Edge/Undo: (pick one of the two lines within the

circle)

<Select object to trim>/Project/Edge/Undo: (pick the other line within the circle)

<Select object to trim>/Project/Edge/Undo:

To Draw the Text

Command: DTEXT

Justify/Style/<Start point>: J


Align/Fit/Center/Middle/Right/TL/TC/TR/ML/MC/MR/BL/BC/BR: M

Middle point: CEN

_cen of : (pick a point on the circumference of the circle)

Height <15.0000>: 15

Rotation angle <0>: 0

Text: N

Text:

Command:

d) Follow the step carefully

i. Begin a New drawing. Turn ON the Snap ( F9 ) and Grid ( F7 ). Draw two circles, each with a 1.5 unit radius. The circle centers are at 3,5 and 5,5 See Figure 3.24

Figure 3.24

ii. Use Zoom All. Does the display change? Now use Zoom Extents. What happens? Now use Zoom All again. Which option always showns all the limits?

iii. Draw a circle with the center at 10,10 and with a radius of 5. now use Zoom All. Notice the Grid only appears on the area defined by the limits. Can you move the cursor to 0,0? Now use Zoom Extents. What happens? Can you move the cursor to 0,0?

iv. Erase the large circle. Use Zoom All. Can you move the cursor 0,0? Use Zoom Extents. Can you find point 0,0?


e) Open the file C:\Program files\AutoCAD R14\Sample\azimuth.dwg. The drawing

looks like the following figure

Figure 3.25: Azimuth.dwg File Using Zoom and Pan command, please show how the figures below look.

Figure 3.26

Figure 3.27

Figure 3.28


FEEDBACK TO SELF ASSESSMENT

Discuss your answers with your lecturer

E2004/4/1 DRAW COMMANDS

UNIT 4

DRAW COMMAND

OBJECTIVES

General Objective : To understand and apply the concept of draw commands

Specific Objectives : At the end of this chapter you should be able to:

Use and invoke the draw commands.

Draw Lines by the Line command.

Make Arc by using Arc command with 10 different method.

Draw Circles by five options method.

Makes Polylines by using Pline command.

Create an ellipse with three methods.

Draw Polygon, Donut and Solid by using Draw Comand.


INPUT 4a

4.0 INTRODUCTION

Draw commands create objects. An object is the smallest component of a drawing. The draw commands listed immediately below create simple objects and are discussed in this unit. Simple objects appear as one entity. Line, Circle, Arc, Point Other draw commands create more complex shapes. Complex shapes appear to be composed of several components, but each shape is usually one object. An example of an object that is one entity but usually appears as several segment is listed below;

Pline Other draw commands are combination of simple and complex shapes:

Xline, Polygon, Rectangle, Donut, Spline, Ellipse, Divide, Mline, Solid

Normally, there are three methods that can be used to access draw commands. We can use either draw toolbar, keyboard entry of the command or pull-down menu ( Figure 4.1 ).


Draw Toolbar

Pull-Down Menu

Keyboard Entry

Figure 4.1: Three methods of using draw commands entry

DRAW COMMANDS 4.1 Line

This is the fundamental drawing command. Use the line command to construct a line from one endpoint to the other. One or several line segments can be drawn with the line command. You can specify the endpoints of lines using two-dimensional or three-dimensional coordinates.

Draw toolbar : Menu : Draw > Line Command line : line or type “L” From point: Specify a point or press ENTER to continue from the last line or arc To point: Specify a point To point: Specify a point, enter u or undo, enter c or close, or press ENTER AutoCAD draws a line segment and continues to prompt for points. You can draw a continuing series of line segments, but each line segment is a separate object. Press ENTER to end the command.


For example, the following command sequence draws a single line segment ( figure 4.2 ).

Command : line From point : Specify a point (1) To point : Specify a point (2) To point : Press ENTER

Figure 4.2

1

2

4.2 ARC

An arc is part of a circle; it is a regular curve of less than 360 degrees. The arc command in AutoCAD provides eleven options for creating arcs. An arc is one object. Arcs are always drawn by default in a counter-clockwise direction. An arc command can be reached by the following way

Draw toolbar : Pull-down menu : Draw > arc Command : arc There are a number of ways to create arcs. The 3 points arc option is the default for the ARC command. 3 point arc

This command option identifies the location of the 3 points of the arc. We can use the keyboard and specify the coordinates or we may use the mouse to point the coordinates.


Figure 4.3 Start, Center, End The radius is defined by the first two points that you specify.

Figure 4.4 Start, center, angle The angle is the included angle between the sides from the center to the endpoints. A negative angle can be entered to generate an Arc in a clockwise direction.

Figure 4.5 : Start, Center, Length Length means length of chord. The length of chord is between the start and the other point specified. A negative chord length can be entered to generate an arc of 180+ degrees.


Figure 4.6 Start, end, angle The included angle is between the sides from the center to the endpoints. Negative angles generate clockwise arcs. The angle for figure below is 70 degrees.

Figure 4.7 Start, end, radius The radius can be picked or entered as a value. A negative radius value generates arcs of 180+ degrees.

Figure 4.8


Start, end, direction The direction is tangent to the start point.

end

direction

start

Figure 4.9 Center, start, end The option is like start, center, end but in a different order.

end start

center Figure 4.10 Center, start, angle This option is like start, center, angle but in a difference order.

angle

start center


Figure 4.11 Center, start, length This is similar to the start, center, length option but in a different order. Length means length of chord.

center

start

Length

Figure 4.12 Continue The new Arc continues from and is tangent to the last point. The only other point required is the endpoint of the arc. This method allows drawing arcs tangent to the preceding Line or Arc. 4.3 Circle The CIRCLE command has many options, these include center, radius; center, diameter; two points, three points; tangent, tangent, radius; tangent, tangent, tangent.

Draw toolbar : Menu : Draw > Circle Command line : circle

Circle by Radius Mode: Use the Circle command and the Radius mode to construct a circle by a radius value specified by the user. After selecting a center point for the circle, the user is prompted to enter a radius for the desired circle. Study the prompt below and illustration for constricting a circle using the Radius mode.


Command : CIRCLE 3P/2P/TTR/<Center Point> : ( Mark the center at ‘A’ ) Diameter/<Radius> : 1.50

Figure 4.13 Circle by Diameter Mode Use the Circle command and the Diameter mode to construct a circle by a diameter value specified by the user. After selecting a center point for the circle, the user is prompted to enter a diameter for the desired circle. Study the prompt and illustration below for constructing a circle by using Diameter mode.

Figure 4.14 Command : CIRCLE

3P/2P/TTR/<Center Point> : ( Mark the center at ‘A’ ) Diameter/<Radius>: Diameter Diameter : 3.00


3 Point Circle Mode: Use the CIRCLE command and the 3 Point mode to construct a circle by 3 points identified by user. No center point is required when entering the 3 Point mode. Simply select three points and the circle is drawn. Study the prompt and illustration below for constructing a circle using the 3 Point mode.

Command : CIRCLE

3P/2P/TTR/<Center Point> : 3P First Point : ( Select the Point at ‘A’ ) Second point : ( Select the Point at ‘B’ ) Third point : ( Select the Point at ‘C’ )

( B )

( A ) ( C )

Figure 4.15 2 Point Circle mode: Use the Circle command and the 2 Point mode to construct a circle by selecting 2 points. These points will form the diameter of the circle. No center point is required after entering the 2 point mode. Study the prompt and illustration below for constructing a circle by using the 2 Point mode.

Command : CIRCLE 3P/2P/TTR/<Center Point> : 2P First Point : ( Select the Point at ‘A’ ) Second point : ( Select the Point at ‘B’ )


Figure 4.16 Tangent-Tangent-Radius Mode - Method # 1: This mode is very powerful when constructing a circle tangent to two entities. Illustrated below is an application of using the TTR mode to construct a circle tangent to two line segments. Study the prompt below to create this type of circle.

Command : CIRCLE 3P/2P/TTR/<Center Point> : TTR Enter tangent spec : ( Select the line at ‘A’ ) Enter second tangent spec : ( Select the line at ‘B’ ) Radius : 1.4

B

( A )

A

( B )

Figure 4.17 Tangent-Tangent-Radius Mode : Method # 2:


Illustrated below is an application of using the Circle TTR mode to construct a circle tangent to the line segment on another circle. Study the prompt below to create this type of circle.

Command : CIRCLE 3P/2P/TTR/<Center Point> : TTR Enter tangent spec : ( Select the line at ‘A’ ) Enter second tangent spec : ( Select the circle at ‘B’ ) Radius : 1.3

( B ) ( A )

Figure 4.18

Tangent-Tangent-Radius Mode : Method # 3: Illustrated below is an application of using the Circle TTR mode to construct a circle tangent to another two circle. Study the prompt below to creating this type of circle.

Command : CIRCLE

3P/2P/TTR/<Center Point> : TTR Enter tangent spec : ( Select the circle at ‘A’ ) Enter second tangent spec : ( Select the circle at ‘B’ ) Radius : 1.00


( A )

( B )

Figure 4.19 4.5 POINT

Use the point command to identify the location of a point on a drawing. This point may be

used for reference purposes. The Osnap-Node or Nearest options are used to snap to points.

By default, a point is displayed as a dot on the screen. This dot may be confused with the

existing grid dots already on the screen. To distinguish point entities from grid dots, use the

chart at the right to assign a new point type; this is accomplished through the Pdmode

system variable. Entering a value of 3 for Pdmode display the point as an ‘X’. The Pdsize

system variable controls size of the point. Use the prompts below for changing the point

mode to a value of 3.

Command : Pdmode

New value for variable PDMODE <0> : 3

Command : Point

Point : ( Mark the new position of a point using the cursor or one of the many

coordinate systems )

Use the DDPTYPE dialog box below for dynamically selecting a new point mode and point

size.


Figure 4.20 : Point Style dialog box


ACTIVITY 4a


4.1 Draw the figure below with line, arc and circle command.

Figure 4.21

Figure 4.22




INPUT 4b

4.4 POLYLINE Polilyne is similarly to individual line segment except that a polyline may consists of

numerous segments and still be considered as a single entity. Width may also be assigned to

a polyline compared to regular line segment, which makes polylines perfect for drawing

border and title block. Study both command sequences below for using the Pline command.

Command : Pline

From point : ( Select a point at ‘A’ )

Current line-width is 0.0000

Arc/Close/Halfwidth/Length/Undo/Width/<endpoint of line>:

( Mark a point at ‘A’ )


Width

Starting width <0.0000>: 0.10

Ending width < 0.0000> : ( Strike Enter to accept default )


( Mark a point at ‘B’)


( Mark a point at ‘C’)


( Mark a point at ‘D’)



( Mark a point at ‘E’)


( Strike Enter to exit this command)

B

C D

A E

Four segment are representing one polyline entity.

Figure 4.22

Command : Pline

From point : ( Select a point at ‘A’ )

Current line-width is 0.0000


@1.00<0( to ‘B’ )


@2.00<90 ( to ‘C’)


@0.50<0( to ‘D’)


@0.75<90( to ‘E’)


@0.75<180( to ‘F’)


Close


Figure 4.23 4.6 ELLIPSE

An Ellipse is one object. There are three methods of creating Ellipse In AutoCAD.:

• Specify one axis and the end of the second.

• Specify the center and the ends of each axis.

• Create an ellipse arc.

Each option also permits supplying a rotation angle than the second axis length.

Toolbar :

Pull-down menu : DRAW > ELLIPSE

Command : ELLPISE

Command : ellipse

Arc/Center/<Axis Point1> : PICK or (coordinates) (This is the first

endpoint

of either the major or minor axis.)

<Other axis distance>/Rotation: PICK or (coordinates) ( This distance is

measured perpendicularly from the established axis )


Axis End This default option requires Picking three points as indicated in the command

sequence above.

Figure 4.24 Rotation If the rotation option is used with the Axis End method, the following syntax is used:

<Other axis distance>/Rotation : R

Rotation around major axis : PICK or (value)

Rotation = 45º

Figure 4.25

The specified angle is the number of degrees the shape is rotated from the circular

position.

Center

With many practical applications, the center point of the ellipse is known, and

therefore the center option should be used.


Command : ellipse

Arc/Center/<Axis endpoint1> : C

Center of ellipse : PICK or (coordinates)

Axis endpoint : PICK or (coordinates)

<Other axis distance>/Rotation : PICK or (coordinates) ( This distance is

measured perpendicularly from the established axis )

The Rotation option appear and can be invoked after specifying the Center first Axix

endpoint.

Figure 4.26

Arc

Use this option to construct an elliptical arc ( partial ellipse ). The procedure is

identical to the Center option with the addition of specifying the start and endpoint

for the arc.

Command : ellipse

Arc/Center/<Axis endpoint 1>: a

<Axis endpoint 1>/center: PICK or (coordinates)

Axis endpoint 2 : PICK or (coordinates)

<Other axis distance>/Rotation : PICK or (coordinates)

Parameter/<start angle>: PICK or (angular value)

Parameter/Included/<end angle> :PICK or (angular value )

Command :


Figure 4.27

4.7 POLYGON

The polygon command is used to construct a regular polygon. Polygons are

defined by the radius of circle which classifies the polygon as either being inscribed

or circumscribed. Polygons consist of a closed polyline entity with width set to zero.

The following prompt sequence is used to construct an inscribed polygon with the

illustration as a guide.

Toolbar :

Pull-down menu : Draw > polygon

Command : POLYGON

Command : Polygon

Number of sides : 6

Edge/<Center of polygon>: ( Select a point at ‘A’ )

Inscribed in circle/Circumscribed about circle ( I/C ) : Inscribed

Radius of circle : 1.00


Figure 4.28

The following prompt sequence is used to construct a circumscribed polygon with

the illustration as a guide.

Command : Polygon

Number of sides : 6

Edge/<Center of polygon>: ( Select a point at ‘A’ )

Inscribed in circle/Circumscribed about circle ( I/C ) : Circumscribed

Radius of circle : 1.00

Figure 4.29

Polygon may be specified by locating the endpoints of one of its edges. The polygon

is then drawn in a counterclockwise direction. Study the illustration at the right and

the prompt sequence below for constructing a polygon by one of its edges.


Command : Polygon

Number of sides : 6

Edge/<Center of polygon>: Edge

First endpoint of edge : ( Select a point at ‘A’)

Second endpoint of edge : ( Select a point at ‘B’ )

Figure 4.30

4.7 DONUT

Use the Donut command to construct a filled-in circle. This entity actually

resembles a polyline. The illustration below is an examples of a donut with an inside

diameter of 0.50 units and an outside diameter of 1.00 units. When placing Donut in

a drawing, the multiple option is automatically invoked. This means you can place as

many donuts as you like until another command is selected from one of the three

menu areas or a “Cancel” or CTRL-C is issued.

Command : Donut

Inside Diameter<0.50>: ( Strike Enter to accept the default )

Outside Diameter<1.00>: ( Strike Enter to accept the default )

Center of donut : ( Select a point to place the donut )

Center of donut : ( Select a point to place the donut or strike Enter to exit this

command )


0.50

1.00

Figure 4.31

Set the inside diameter of a donut to a value of zero ( 0 ) and an outside diameter to

any other values to constructs a donut representing a dot.

Command : Donut

Inside Diameter<0.50>: 0

Outside Diameter<1.00>: 0.25

Center of donut : ( Select a point to place the donut )

Center of donut : ( Select a point to place the donut or strike Enter to exit this

command )

4.8 SOLID

The Solid command allows the user to create a fill in area of quadrilateral or

triangular shapes. Two endpoints or intersections are picked as a starting edge of the

solid. Two additional endpoints or intersections complete the opposite edge of the

solid. Study the following prompt sequence and the illustration for creating a solid.

Command : Solid

First point : ( Select the intersection at ‘A’ )

Second point : (Select the intersection at ‘B’ )

Third point : ( Select the intersection at ‘C’ )

Fourth point : ( Select the intersection at ‘D’ )

Third point : ( Strike Enter to exit this command )


( B ) ( A )

( C ) ( D )

Figure 4.32

It is important how the second solid edge is selected. Instead of the third point being

selected diagonally from the second point as in the illustration, it was selected

adjacent to the second point. This created the ‘hourglass’ shape familiar to first-time

users of the Solid Command.

Command : Solid






( B ) ( A )

( C ) ( D )

Figure 4.33


Solid edges may be continuously selected as in the illustration below. The key is that

the third point is picked opposite or diagonally from the second point. Follow the

prompt sequence below to create this type of multiple solid.

Command : Solid





Third point : ( Select the intersection at ‘E’ )

Fourth point : ( Select the intersection at ‘F’ )

Third point : ( Select the intersection at ‘G’ )

Fourth point : ( Select the intersection at ‘H’ )


( E ) ( C )

( D ) ( F )

( B ) ( A ) ( H ) ( G )

Figure 4.34


ACTIVITY 4b EXERSICE.

4.2 In this exercise, you use the POLYGON, RECTANGULAR, DONUT, and

ELLIPSE command to draw whirlpool fixture. Try this following step to

complete your exercise.

A) Creating rectangular

1. From the File menu, choose New.

2. Choose the Start From Scratch button, under the Select Default Setting

list, select Metric, then choose OK.

3. From the Draw menu, choose Rectangular

4. Enter 0,0 at the First corner : Command Prompt. Then press ENTER

5. Enter 96,60 at the Other corner : Command prompt

6. Enter 2,29 at the First corner : Command Prompt

7. Enter 10,31 at the Other corner : Command Prompt. Then press ENTER

8. From the View menu, choose Zoom, then choose Extents

B) Using the ELLIPSE command

1. To draw an Ellipse, enter el at the command prompt.

2. Enter 5,30 at the Arc/Center/<Axis endpoint 1>: Command prompt. Then

press ENTER.


3. Enter 91,30 at the Axis endpoint 2 : Command prompt, then press enter.

4. Enter 25 at the <Other axis distance>/Rotation : Command prompt. Then

press ENTER.

C) Using the POLYGON command

1. From the Draw menu, choose POLYGON.

2. At the Number of sides <4> : Command prompt, enter 6, then enter 3,24

at the Edge/<Center of Polygon> : Command prompt.

3. Enter i for inscribed, then enter 2 for radius. Press ENTER twice.

4. At the Number of sides <4> : Command prompt enter 6, then enter 3,36

at the Edge/<Center of Polygon> : Command prompt.

5. Enter i for inscribed, then enter 2 for radius. Then press ENTER.

D) Using the DONUT command

1. From the Draw menu, choose DONUT

2. At the Inside Diameter : Command prompt, enter 2.5

3. Enter 10 at the Outside diameter : Command prompt.

4. At the Center of doughnut : Command prompt, enter 48,30. Then press

ENTER.



ANSWERS 4.2

Figure 4.35


ANSWER ALL THE QUESTIONS BELOW. QUESTION 4-1 :

a) List all the options to draw an arc under the Arc Command.

b) Give the suitable method to construct a circle tangent to the line segment on another circle.

c) Give the options to draw a polygon and what is the different between it? QUESTION 4-2 : a) Draw the figure below with suitable command.


b) Draw the circuit as in figure in Schematic diagram without scale with the suitable command

Figure 4.37


FEEDBACK TO SELF ASSESSMENT ANSWER 4-1 a) There are 11 options to draw an Arc under Arc Command:

* 3 point arc * Start, Center, End * Start, center, angle * Start, Center, Length * Start, end, angle

* Start, end, radius * Start, end, direction

* Center, start, end * Center, start, angle * Center, start, length * Continue

b) TTT – Tangent - Tangent – Radius Mode c) They are 3 options to draw a polygon

• Inscribe of Circle


• Circumscribed about a Circle

• A Polygon by edge

E2004/5/1 MODIFY COMMANDS

UNIT 5

MODIFY COMMAND

OBJECTIVES

General Objective : To understand the concept of Modify commands

Specific Objectives : At the end of this chapter, you should be able to:

Locate and invoke the Modify command

Erase objects from the drawing.

Move objects from a base point to a second point

of a displacement.

Rotate objects about a basepoint.

Enlarge or reduce objects with scale.

Make mirror images of selected objects.

Make rectangular and polar arrays of existing objects

Stretch selected object.

Trim away parts of objects at cutting edges.

Extend objects to selected boundary edges.

Create a fillet between two objects.

Create a Chamfer between two objects.

Create parallel copies of objects with offset.


INPUT 5a

5.0 INTRODUCTION

Draw commands are used to create new objects. Modify commands or edit commands are used to change existing objects or to use existing objects to create new and similar objects. The commands listed below are covered in this unit:

5.1 Erase 5.2 Move 5.3 Rotate 5.4 Trim 5.5 Scale 5.6 Mirror 5.7 Array 5.8 Stretch 5.9 Extend 5.10 Fillet 5.11 Chamfer 5.12 Offset 5.13 Divide 5.14 Measure 5.15 Change 5.16 Pedit


5.1 ERASE

The erase command deletes the objects you select from the drawing. Any of the object

selection methods can be used to highlight the object to erase. The only other required

action is press Enter to cause the erase to take effect.

Methods for invoking the ERASE command include:

Toolbar :

Pull-down Menu : Modify > Erase

Command : Erase

An example of the erase command prompt is as follows:

Command: Erase

Select Objects: PICK (Use any object selection method.)

Select Objects: PICK (Continue to select desired objects)

Select objects: Enter (Confirm the object selection process and causes Erase

to take effect. )

Command:

If objects are erased accidentally, U or Undo command can be used immediately following

the mistake to undo one step, or oops can be used to bring back into the drawing whatever

was erased the last time erase was used.

5.2 MOVE

Move allows you to relocate one or more objects from the existing position in the

drawing to any other position you specify. After selecting the objects to move, you must

specify the base point and second point of displacement.


Methods for invoking the MOVE command include:

Toolbar :

Pull-down menu : Modify > Move

Command : Move

The prompts for the MOVE command are as follows:

Command: move

Select objects: ( Select objects you want to move )

Select objects: ( Press ENTER )

Base point or displacement: ( Select a point )

Second point of displacement: ( Select a point )

Example

In the following figure, you want to put a corner of the rectangle at the center of the

circle.

Command: move

Select objects: 1 found ( select the rectangle )

Select objects: ( Press ENTER )

Base point or displacement: end of ( Select the corner of the rectangle )

Second point of displacement: center of ( Select any point on the circle

circumference )

Command:


Figure 5.1 : Using MOVE Command to put the rectangle at the center of the circle

5.3 ROTATE

Selected object can be rotated to any position with this command. After selecting

object to rotate, you select a “basepoint” ( a point to rotate about ) then specify an

angle for rotation.

Methods for invoking the ROTATE command include:

Toolbar :

Pull-down menu : Modify>rotate

Command : Rotate

An example of the ROTATE command prompt is as follows:

Command: rotate

Select Object: ( Specify the objects to rotate )

Base Point : end of ( Specify the basepoint )

< Rotation angle>/Reference:


Figure 5.2: Using the ROTATE command to rotate the rectangle about 900 from

basepoint

5.4 TRIM

The Trim command allows you to trim ( shorten ) the end of end object back

to the intersection of another object ( figure ). The middle section of an object can

also be trimmed between two intersection objects. There are two steps to this

command;

1. PICK one or more “cutting edge” ( existing object )

2. Then PICK the object or objects to trim ( portion to remove )

The cutting edges are highlighted after selection. Cutting edges themselves can be

trimmed if they intersect with other cutting edges, but lose their highlight when

trimmed.

Methods for invoking the TRIM command include:

Toolbar :

Pull-down menu : MODIFY > TRIM

Command : TRIM


An example of the erase command prompt is as follows:

Command: trim

Select cutting edges: ( Projmode = UCS, Edgemode = No Extend)

Select Objects: PICK ( Select an object to use as a cutting edge )

Select Objects: PICK

Select Objects: Enter

< Select object to trim >/Project/Edge/Undo:PICK ( select the end of and object to

trim )

< Select object to trim >/Project/Edge/Undo: PICK

< Select object to trim >/Project/Edge/Undo:Enter

Command:

Figure 5.3: Using TRIM command to trim the objects.


ACTIVITY 5a

EXERCISES.

5.1 Begin a New drawing and create the geometry in Figure 5.4 using Lines and Circles.

If desired, set SNAP to .25 to make drawing easy and accurate.

For practice, turn SNAP OFF ( F9 ). Use the Move command to move the circles and

lines into the position shown in illustration B. OSNAPs are required to Move the

geometry accurately. Save the drawing as MOVE1.

Figure 5.4

a

b


5.2 Begin a New drawing and create the geometry in Figure 5.5 Rotate the shape into

position shown in step B. Save As ROTATE1.

Use the reference option to Rotate the box to align with the diagonal Line as shown

in C. Save As ROTATE2.

Figure 5.5

5.3 Trim command

i. Create the shape shown in figure 5.6 A Save As TRIM-EX

ii. Use Trim to alter the shape as shown in B Save As TRIM1

iii. Open TRIM-EX to create the shapes shown in C and D using Trim. Save As

TRIM2 and TRIM3.

Figure 5.6


Feedback To Activity 5a

Answers

5.1 Step to Modify Figure 5.4 (A) to get the geometry Figure 5.14 (B) using ‘Move command’

Command: MOVE ( to move the lines )

Select objects: 1 found ( select ‘a’ line )

Select objects: 1 found ( select ‘b’ line )

Select objects: ( enter to finished the selection)

Base point or displacement: end of ( select end of right horizontal line )

Second point of displacement: mid of ( select mid of right horizontal line )

Command: MOVE ( to move the first circle )

Select objects: 1 found ( select first circle )

Select objects: ( enter )

Base point or displacement: qua of ( select 90 degree quadrant for circle 1.5

diameter )

Second point of displacement: mid of ( select mid point of ‘a’ line )

Command: MOVE ( to Move second line )

Select objects: 1 found

Select objects: ( enter )

Base point or displacement: cen of ( center of the 1.0 diameter circle )

Second point of displacement: int of ( center of ‘b’ line )

Command: ( enter )

5.2 Draw carefully and after that discuss with your lecturer.

5.3 Draw carefully and after that discuss with your lecturer


INPUT 5b

5.5 SCALE The scale command is used to increase or decrease the size of objects in a drawing. The

scale command does not normally have any relation to plotting a drawing to scale.

Methods for invoking the SCALE command include:

Toolbar :

Pull-down menu : MODIFY > SCALE

Command : SCALE

An example of the scale command prompt is as follows:

Command : scale

Select Object : PICK or ( coordinates) ( Select the object to scale )

Select Object : ENTER ( Indicates completion of the object selection )

Base point : PICK or ( coordinates ) ( Select the stationary point)

Scale factor <Reference>: PICK or (value) or (coordinates) ( Enter a value for the

scale factor or interactively scale the set of object)

Command :


Figure 5.7 : Using SCALE Command to enlarge the rectangle with scale factor;2

5.6 MIRROR

This command creates a mirror image of selected existing objects. You can retain or delete

the original objects ( ‘old object’ ). After selecting objects, you create two points specifying

a ‘rubberband line’, or ‘mirror line’, about which to mirror.

Methods for invoking the MIRROR command include:

Toolbar :

Pull-down menu : MODIFY > MIRROR

Command : MIRROR

An example of the scale command prompt is as follows:

Command : mirror

Select Object : PICK ( Select object or group of object to mirror )

Select Object : Enter ( Press Enter to indicate completion of object selection. )

First point of mirror line : PICK or (coordinates) (Draw first endpoint of line to

represent mirror axis by PICKing or entering coordinates)

Second point of mirror : PICK or (coordinates) (Draw second point of line by

PICKing or entering coordinates)


Delete old objects ? <N> Enter or Y ( Press Enter to yield both sets of objects or

enter Y to keep only the mirrored set.)

Command :

5.7 ARRAY

The array command creates either a Rectangular or Polar ( circular ) pattern of

existing object that you select. The pattern could be created from a single or from a group of

objects. Array copies a duplicate set of objects for each ‘item’ in the array.

Methods for invoking the ARRAY command include:

Toolbar :

Pull-down menu : MODIFY > ARRAY

Command : Array

Rectangular

This option creates an Array of the selection set in a pattern composed of rows and

columns. The command syntax for a rectangular is given next:

Command : Array

Select Objects : PICK ( Select object to be arrayed )

Select Objects : Enter ( Indicates completion of object selection)

Rectangular or Polar array (<R>/P) : R (indicates rectangular )

Number of rows (---)<1> : (value) ( enter value for number of rows)

Number of columns (lll)<1> : (value) (enter value for number of columns)

Unit cell or distance between rows (---): ( value) ( enter a value for the

distance from any of one object to the same point on an object in the adjacent

row.

Distance between columns (lll) : (value ) (enter a value for the distance from

any point on one object to the same point on an object in the adjacent

column.


Command :

s

Figure 5.8: Using Array with Rectangular option

Polar

This option creates a circular pattern of the selection set with any number of copies

or ‘items’. The number of item specified includes the original selection set. You also

specify the center of the array, angle to generate the array through and orientation of

‘item’.

Command : Array

Select Object : PICK ( select object to be arrayed)

Select Object : Enter

Rectangular or Polar array ( <R>/P ) : P (indicates Polar array)

Center point of array : PICK ( select point from array to be generated around)

Number of items : ( value ) ( enter value for number of copies including

original selection set )

Angle to fill (+=ccw,-=cw) <360>: Enter or (value) (press enter for full

circular array, enter value for less than 360 degree array; enter negative value

for clockwise generation array)

Rotate object as they are copied? <Y> Enter or N (Press Enter for rotation of

copies object about center, N for keeping objects in original orientation.)


Figure 5.9 : Using ARRAY Command with polar option

5.8 STRETCH

Object can be made longer or shorter with STRETCH. When ‘Stretched’,Line and Plines

become longer or shorter and Arc change radius to become longer or shorter. Circle do not

stretch; rather, they move if the circle is selected within the Crossing Window.

Methods for invoking the STRETCH command include:

Toolbar :

Pull-down menu : MODIFY > STRETCH

Command : STRETCH

An example of the stretch command prompt is as follows:

Command : STRETCH

Select Object(s) : to stretch by crossing-window or polygon

Select Object :

First Corner : PICK

Other Corner : PICK


Select Object : Enter

Base point or displacement : PICK or (coordinates ) ( Select a point to use as the

point to stretch from. )

Second point of displacement : PICK or (coordinates) (Select a point to use as the

point to stretch to)

Command :

Figure 5.10 : Stretching the drawing


ACTIVITY 7b

EXERCISES.

5.4 Begin a New drawing and create the geometry in Figure 5.11 (A). Then Scale the

shape by a factor of 1.5. Now the geometry look like Figure 5.11 (B)

Figure 5.11

5.5 A manufacturing cell is displayed in Figure 5.12 The view is from above, showing a

robot centered in a work station. The production line requires 4 cells. Begin by

starting a New drawing, setting Units to Engineering and Limits to 40’ x 30’. Draw

one cell to the dimensions indicated. Begin at the indicated coordinates of the lower-

left corner of the cell. SaveAs ROBOT1.

Figure 5.12


Use Mirror to create the other three manufacturing cells as shown in Figure 5.13

Ensure that there is sufficient space between the cells as indicated. Draw the two

horizontal Lines representing the walkway as shown. Save the drawing.

Figure 5.13

5.6 A design change has been requested. Open ROBOT1 drawing and make the

following changes

The top of the workstation ( work area for the robot ) must be move upward. This

design change will add 3 inches to the total height of the workstation. Use Stretch to

accomplish the change. Then save the drawing as ROBOCHANGE. The figure

below shown the new workstation

Figure 5.14


5.7 Begin a New drawing. Select Start from Scratch, English defaults. Create the start -

ing geometry for a Flange Plate as shown in Figure 5.15 Save As ARRAY.

Figure 5.15

i. Create the Polar Array as shown in Figure 5.16 A. Save As ARRAY1

ii. Open ARRAY. Create the Polar Array as shown in Figure 5.16 B. SaveAs

ARRAY2. (HINT: Use a negative angle to generate the Array in a clockwise

direction.)

Figure 5.16


5.8 Using Array with Rectangular option

i. Begin a New drawing. Select Start from Scratch, Metric setting. Use Save and

assign the name LIBDESKS.

ii. Create the Array of study carrels (desks) for the library as shown in Figure 5.17

Draw the first carrel Each carrel is 30 x 42. Design your own chair.

iii. Create the Rectangular Array so that the carrels touch side to side and allow a 25

aisle for walking between carrels (not including chairs).

Figure 5.17



Please discuss with your lecturer if you have any problem.


INPUT 5C

5.9 EXTEND

Extend can be thought of as the opposite of Trim. Objects such as Lines, Arc, and

Pline can be extended until intersecting another object called a ‘boundary edge’ as in Figure

5.18. The command first requires selection of existing object to serve as ‘boundary edge(s)’,

which become highlighted, then the objects to extend are selected. Objects extend until, and

only if, they eventually intersects ‘boundary edge’. An Extended object acquires a new

endpoint at the boundary edge intersection.

Methods for invoking the EXTEND command include:

Toolbar :

Pull-down menu : MODIFY > EXTEND

Command : Extend

Command : extend

Select boundary edges : (Projmode = UCS, Edgemode = No extend )

Select Objects : PICK

Select Objects : PICK

Select Objects : Enter

<Select object to extend>/Project/Edge/Undo: PICK ( Select object to

extend)

<Select object to extend>/Project/Edge/Undo: PICK

<Select object to extend>/Project/Edge/Undo: Enter

Command :


Figure 5.18

Edge mode/Project mode

The edge mode and Project mode switches operate identically to their function with

the Trim command. Use Edge mode with the Extend option if you want a boundary

edge object to be imaginarily extended.

Figure 5.19


5.10 FILLET

The fillet command automatically rounds a sharp corner ( intersection of two Lines,

Arcs, Circles, or Pline vertices ) with a radius. You only specify the radius and select the

objects to be filleted. The objects to fillet do not have to completely intersect but can

overlap. You can specify whether or not the object are automatically extended or trimmed as

necessary ( Figure 5.20 )

Methods for invoking the FILLET command include:

Toolbar :

Pull-down menu : MODIFY > FILLET

Command : Fillet

The fillet command is used first to input the desired radius ( if other than the default 0.500

value ) and a second time to select the object to fillet.

Command: fillet

( TRIM Mode ) Current fillet radius = 0.5000

Polyline/Radius/Trim/<Select first object>: r ( Indicates the radius option )

Enter fillet radius < 0.5000>: ( value ) or PICK ( Enter a value for the desired

fillet radius or select two points to interactively specify the radius )

Command:

Figure 5.20


5.11 CHAMFER

Chamfer is a manufacturing process used to replace a sharp corner with an angled

surface. In AutoCAD, Chamfer is commonly used to change the intersection of two Lines or

Plines by adding an angled line. The Chamfer command is similar to fillet, but rather than

rounding with a radius or “fillet”, an angled line is automatically drawn at the distances

( from the existing corner ) that you specify.

Methods for invoking the CHAMFER command include:

Toolbar :

Pull-down menu : MODIFY > CHAMFER

Command : Chamfer

Chamfer can be created by two methods: Distance ( specify two distances ) or Angle

( Specify a distance and an angle ).

Distance option is used to specify the two values applied to create the chamfer. The value

indicate the distances from the corner ( intersection of the two line ) to each chamfer

endpoint ( Figure 5.21 ). Use the chamfer command once to specify distances and again to

draw the chamfer.

Command: chamfer

(TRIM Mode ) Current chamfer Dist1 = 0.0000, Dist2 = 0.0000

Polyline/Distance/Angle/Trim/Method/<Select first line>:d ( Indicates the distance

option )

Enter first chamfer distance<0.0000>: ( value ) or PICK

Enter second chamfer distance <value of first distance>: Enter or PICK

Command:


FIRST DISTANCE

SECOND DISTANCE

Using Distance method

Using Angle Method

Figure 5.21

5.12 OFFSET

Offset creates a parallel copy of selected object. Selected object can be Lines, Arcs, Circles,

Plines or other objects. Two options are available with offset; offset a specified distance and

offset through a specified point.

Methods for invoking the OFFSET command include:

Toolbar :

Pull-down menu : MODIFY > OFFSET

Command : Offset


Figure 5.22

5.13 DIVIDE DIVIDE marks off a specified number of equal lengths on a selected object by placing point

objects or blocks along the length or perimeter of the object. Valid objects that can be

divided include arcs, circles, ellipses and elliptical arcs, polylines, and splines.

Methods for invoking the DIVIDE command include:

Pull-down menu : DRAW > POINT>DIVIDE

Command : Divide

1 From the Draw menu, choose Point Divide.

2 Select a line, arc, spline, circle, ellipse, or polyline.

3 Enter the number of intervals you want to represent.

AutoCAD places a point at each interval on the object.

The point objects that are added to the object can be used for subsequent

construction by allowing you to OSNAP to equally spaced intervals ( Nodes ). After using

the Divide Command, the point objects may not be visible unless the point style is changed

with the Point Style… dialog box ( Format pull-down menu ). A Regen must be invoked

before the new Point style will be displayed. Figure 5.23 below shows Points displayed at

the object.


Figure 5.23

5.14 MEASURE

The Measure command will take an entity such as a line or arc and the

measurement along it depends on the length of the segment. It similar with divide

command, accomplishes this by placing a point entity at a specified distance given in

the measure command.

Methods for invoking the MEASURE command include:

Pull-down menu : DRAW > POINT>MEASURE

Command : Measure

Figure 5.24 Using Measure to divide and measure the line with 3.0 inches length.


5.15 CHANGE

Using the change command allows the characteristics of an entity to be

modified. The Change command allows changing three options: Points, Properties

or Text

Methods for invoking the CHANGE command :

Command : Change

Figure 5.23 : Using Change Command with changing point method

This point allows changing the endpoint of an object or endpoints of several objects

to one position:

Command: Change

Select Objects :PICK

Select Object :Enter

Properties/<Change point>:PICK ( Select a point to establish as new

endpoint of all objects)


5.16 PEDIT

This command provides numerous options for editing polylines ( Plines ). The list of

options below emphasizes the great flexibility possible with polylines. The first step

after invoking Pedit is to select Pline to edit.

Methods for invoking the PEDIT command include:

Toolbar :

Pull-down menu : MODIFY > Object > Polyline

Command : Pedit.

An example of the Pedit command prompt is as follows:

Command : Pedit

Select Polyline : PICK (select the polyline for subsequent editing )

Close or Open/ Join/Width/Edit Vertex/Fit/Spline/Decurve/Ltype

gen/Undo/eXit<X>: (option) ( Select the desired option from the screen

menu or enter the capitalized letter for the desired option.

Close

Close connect the last segment with the first segment of an existing ‘open’ Pline,

resulting in a ‘closed’ Pline. (Figure 5.24 ). A closed Pline is one continuous object

having no specific start or endpoint, as opposed to one closed by PICKing points. A

closed Pline reacts differently to the Spline option and to some commands such as

Fillet, Pline option.


Figure 5.24

Open

Open removes the closing segment if the Close option was used previously. ( Figure

5.24 )

Join

This option join, or connect, any Pline, Lines, or Arc that have exact matching

endpoint and add them to the selected Pline ( Figure 5.25 ) Previously closed Plines

cannot be joined.

Figure 5.25

Width

Width allows specification of a uniform width for Pline segment. ( Figure 5.26 ).

Non-uniform width can be specified with the Edit Vertex option.


Figure 5.26

Another methods that available under Pedit Command are Edit vertex, fit,

Spline,Decurve, Ltype gen, Undo and Exit. Please practice that methods


ACTIVITY 5c EXERCISES. 5.9 Open each of the drawing created as solutions for Figure 5.6 ( TRIM1, TRIM2 and

TRIM3 ). Use extend to return each of the drawing to the original form shown in Figure 5.6 A. Save As EXTEND1, EXTEND2 and EXTEND3

5.10 Create the ‘T’ Plate shown in Figure 5.27. Use Fillet to create all the fillets and

rounds as the last step. When finished, Save the drawing as T-PLATE.

Figure 5.27


5.11 Start New Drawing with Metric setting. Then using Offset Command to draw the

entire box in Figure 5.28

Figure 5.28

5.12 Draw the figure below to learn chamfer command

i. Begin a New drawing and select Start from Scratch, English defaults.

ii. Set the Limits to 279,216. Next, type Zoom and use the All option.

iii. Create the Catch Bracket shown in Figure 5.29. Draw the shape with all vertical

and horizontal Lines ( Figure 5.29A )

iv. Use Chamfer to create the six chamfers ( Figure 5.29B ). Save the drawing as

CBRACKET.

BA

Figure 5.29


5.13 Create the table in Figure 5.30 to be used as a bill of materials. Draw the bottom Line ( as dimensioned ) and a vertical Line. Use Divide along the bottom Line and Measure along vertical line to locate Points as desired. Create Offsets through the Points.

Use Measure command to measure with 0.5

Use Divide command to divice with 6 segment

Figure 5.30


FEEDBACK TO ACTIVITY 5c

Draw the figure carefully and then discuss with your lecturer


You are approaching success. Try all the questions in this self-assessment. QUESTION 5-1 :

a) Draw all figures below with all draw and modify commands

i)

Figure 5.31


ii)

Figure 5.32

iii)

Figure 5.33


Feedback To Self-Assessment


E2004/6/1 Text, Dtext, Textstyle

UNIT 6

TEXT, DTEXT AND

TEXTSTYLE

OBJECTIVES

General Objective : To understand and apply the concept of creating and editing text

Specific Objectives : At the end of the unit you will be able to:

Create lines of text in a drawing using Text and Dtext.

Create and format paragraph text using Mtext.

Create text styles with the Style command.


6.0 INTRODUCTION

Annotating a drawing lets you present information that cannot be presented graphically.

This information can be included as text in dimensions, notes, and titles. AutoCAD provides

you with a number of techniques that let you effectively create and place text in a drawing.

Text in technical drawings is typically in the form of notes concerning information

or descriptions of the objects contained in the drawing. For example an architectural

drawing might have writing description of rooms or spaces, special instructions for

construction or notes concerning materials or furnishing. An engineering drawing may

contain in addition to the dimensions, manufacturing notes, or tables.

In AutoCAD, the commands related to creating or editing text include;

Text Places one line of text in a drawing, but the text is not visible until after

pressing Enter

Dtext Places individual lines of text in a drawing and allow you to see each

letter as it is typed

Mtext Places text in paragraph form ( with word wrap ) within a text boundary

and allow many methods of formatting the appearance of the text.

Style

Creates text styles for use with any of the text creation commands. You

can select from font files, specify other parameter to design the

appearance of the letters, and assign a name for each style.

INPUT 6a


6.1 TEXT CREATION COMMANDS

The commands for creating text are formally named Dtext, Mtext and Text ( these are the

commands used for typing ). The Draw pull-down menu provides access to the two

commonly used text commands, Multiline Text… ( Mtext ) and Single-Line Text ( Dtext )

( Figure 6.1 ). Only the Mtext command has an icon button ( by default ) near the bottom of

the draw toolbar ( Figure 6.2 ). The Text command must be typed at the command line.

Figure 6.1 : Getting text from Pull-down menu

Mtext Toolbar

Figure 6.2 : Mtext toolbar

6.1.1 Dtext

Dtext ( Dynamic text ) lets you insert text into an AutoCAD drawing. Dtext displays each

character in the drawing as it is typed. You can enter multiple lines of text without exiting

the Dtext Command. The lines of text do not ‘wrap’.

Methods for invoking the Dtext Command include :

Pull Down-Menu : Draw > Text > Single Line Text

Command : Dtext

If we use the type command, the options are presented below:

Command: dtext

Justify/Style/< Start point>:


Start Point

The start point for a line of text is the left end of the baseline for the text ( Figure 6.3 ).

Height is the distance from the baseline to the top of upper case letters. Additional lines of

text are automatically spaced below and left justified. The rotation angle is the angle of the

baseline ( Figure 6.4 )

Figure 6.3

Figure 6.4

The command sequence for this option is:

Command: Dtext

Justify/Style/<Start point>; PICK or ( coordinates )

Height < 0.20 >: Enter or ( value )

Rotation Angle < 0 >: Enter or ( value )

Text: ( Type the desired line of text and press Enter. )

Text: ( Type another line of text and press Enter. )

Text: Enter

Command:

NOTE: When the “Text;” prompt appears, you can also PICK a new location for the next

line of text anywhere in the drawing.


Justify

If you want to use one of the justification methods, invoking this option displays the choices

at the prompt:

Command: Dtext

Justify/Style/<Start point>: J ( Invokes the justification options.)

Align/Fit/Center/Middle/Right/TL/TC/TR/ML/MC/MR/BL/BC/BR: ( choice ) ( Type

capital letters)

After specifying a justification option, you can enter the desired text in response to the

“Text:” prompt. The text is not justified until after you press Enter.

Align

Aligns the line of text between the two points specified ( P1,P2 ). The text height is adjusted

automatically ( Figure 6.5 )

Figure 6.5

Fit

Fits ( compresses or extends ) the line of text between the two points specified (P1,P2 ). The

text height does not change ( Figure 6.5 )


Center

Centers the baseline of the first line of text at the specified point. Additional lines of text are

centered below the first ( Figure 6.6 ).

Figure 6.6

Middle

Centers the first line of text both vertically and horizontally about the specified point.

Additional lines of text are centered below it (Figure. 6.6 ).

Right

Creates text that is right justified from the specified point ( Figure. 6.6 ).

TL

Top Left. Places the text in the drawing so the top line (of the first line of text) is at the point

specified and additional lines of text are left justified below the point. The top line is defined

by the upper case and tall lower case letters ( Figure. 6.6 ).

TC

Top Center. Places the text so the top line of text is at the point specified and the line(s) of

text are centered below the point ( Figure. 6.6 ).


TR

Top Right. Places the text so that the top right corner of the text is at the point specified and

additional lines of text are right justified below that point ( Figure. 6.6 ).

ML

Middle Left. Places text so that it is left justified and the middle line of the first line of text

aligns with the point specified. The middle line is half way between the top line and the

baseline, not considering the bottom (extender) line ( Figure 6.6 ).

MC

Middle Center. Centers the first line of text both vertically and horizontally about the

midpoint of the middle line. Additional lines of text are centered below that point (Figure

6.6 ).

MR

Middle Right. Justifies the first line of text at the right end of the middle line. Additional

lines of text are right justified ( Figure 6.6 ).

BL

Bottom Left. Attaches the bottom (extender) line of the first line of text to the specified

point. The bottom line is determined by the lowest point of lower case extended letters such

as y, p, q, j, and g. If only upper-case letters are used, the letters appear to be located above

the specified point. Additional lines of text are left justified ( Figure 6.6 ).


BC

Bottom Center. Centers the first line of text horizontally about the bottom (extender) line (

Figure 6.6 ).

BR

Bottom Right. Aligns the bottom (extender) line of the first line of text at the specified

point. Additional lines of text are right justified ( Figure 6.6 ).


ACTIVITY 6a


6.1 What is DTEXT and how we access DTEXT Command.?

6.2 By default the justification mode used by the DTEXT command is left justified.

Study the following prompt sequence to place the text string “ELECTRICAL.”

Start New Drawing and select Start from scratch and select English setting. At

your drawing area mark the “A” and “B” point with the distance 2.0 inches. The

figure below shows “A” and “B” point.

Figure: 6.7: The “A” and “B” Point with a distance of 3 inches

Follow these instruction to learn about DTEXT

a. Command: DTEXT

Justify/Style/<Start point:’: (Pick the point at “A”)

Height <0.20>: 0.40

Rotation angle <0>: (Press Enter to accept this default)

Text: ELECTRICAL

Text: (Press Enter to exit Dtext and return to the command prompt)


b

.

Command: DTEXT

Justify/Style/<Start point>: Justify ( or enter shortcut ‘J’ )

Align/Fit/Center/Middle/Right/TL/TC/TR/ML/MC/MR/BL/BC/BR: TC

Top/center point: (Pick a point at “A”)

Height <0.20>: 0.40


Text: ELECTRICAL


c. Command: DTEXT

Justify/Style/<Start point>: Middle

Middle point: (Pick a point at “A”)

Height <0.20>: 0.40

Rotation angIe <0 >: (Press Enter to accept this default)

Text: ELECTRICAL



d. Command: DTEXT

Justify/Style!<Start point>: Align

First text line point: (Pick the point at “A”)

Second text line point: (Pick the point at “B”)


Text: ELECTRICAL


e. Command: DTEXT

Justify/Style/<Start point>: Fit

First text line point: (Pick the point at “A”)

Second text line point: (Pickthe point at “B”)

Height <0.20>: 0.40


Text: ELECTRICAL


f. Command: DTEXT

Justify/Style/<Start point>: Right

End point: (Pick the point at “A”)

Height <0.20>: 0.40

Rotation angle <0>: (Press to accept this default)

Text: ELECTRICAL




ANSWERS.

6.1 The DTEXT command stands for Dynamic Text mode and allows you to place text

in a drawing and view the text as you typed it in. This command can be selected by

picking “Draw” from the pull-down menu area followed by “Text” and finally

“Single Line Text. Multiline

6.2

a.

Figure 6.8 : Justifying text by default

b.

Figure 6.9 :Justifying text by a center point.

c.

Figure 6.10 : Justifying text by a middle point.

d.


Figure 6.11: Justifying text by aligning the text between two points. The text height is

automatically scaled depending on the length of the points and the number of letters that

make up the text.

e.

Figure 6.12 :Justifying text by fitting the text in between two points and specifying the text

height. Notice how the text appears compressed due to the large text height and short

distance of the text line.

f.

Figure 6.13: Justifying text by a point at the right.


INPUT 6b

6.1.2 TEXT

Text is essentially the same as Dtext except that the text is not dynamically displayed one

letter at a time as you type, but rather appears in the drawing only after pressing Enter. The

other difference is that Dtext repeatedly displays the “Text:” prompt to allow entering

multiple lines of text, whereas Text allows only one line. Otherwise, all the options and

capabilities of Text are identical to Dtext.

Command: text

Justify/Style/<Start point>: PICK

Height <0.2000>: Enter or (value)

Rotation angle <0>: Enter or (value)

Text: sample line of text. (The line of text appears in the drawing after pressing Enter.)

Command:

If you want to type another line of text below the previous line with the Text command, use

Text again, but press ‘Enter’ at the first prompt. The Text command then responds with the

“Text:” prompt, at which time you can enter the next line of text. The new line is

automatically spaced below and uses the same height, justification, and other options as the

previous line.


6.1.3 MTEXT

Multiline Text ( Mtext ) has more editing options than other text commands. You can apply

underlining, color, bold, italic, font, and height changes to individual characters or words

within a paragraph or multiple paragraphs of text.

Mtext allows you to create paragraph text defined by a text boundary. The text

boundary is a reference rectangle that specifies the paragraph width. The Mtext object that

you create can be a line, one paragraph, or several paragraphs. AutoCAD references Mtext

(created with one use of the Mtext command) as one object, regardless of the amount of text

supplied. Like Text and Dtext, several justification methods are possible.

Command: Mtext

Current text style: STANDARD. Text height: 0.2000

Specify first corner: PICK

Specify opposite corner or : PICK or (option)

You can PICK two corners to invoke the Multiline Text Editor, or enter the first letter of

one of these options: Height, Justify, Rotation, Style, or Width. All of the options can also be

accessed within the Multiline Text Editor.

Using the default option the Mtext command, you supply a “first corner” and “opposite

corner” to define the diagonal corners of the text boundary (like a window). Although this

boundary confines the text on two or three sides, one or two arrows indicate the direction

text flows if it “spills” out of the boundary ( Figure 6.14 ).


Figure 6.14

After you PICK the two points defining the text boundary, the Multiline Text Editor appears

ready for you to enter the text ( Figure. 6.15 ). Enter the desired text. The text wraps based

on the width you defined for the text boundary. You can right-click for a menu allowing you

to Cut, Copy, and Paste selected text. Select the OK button to have the text entered into the

drawing within the text boundary.

Figure 6.15: Multiline Text Editor

There are three tabs in the Multiline Text Editor: Character tab, Properties tab , and Find

and Replace tab. Using the options in these tabs is interactive text in the editor immediately

reflects the changes made for most options in these tabs. There is also a button to Import

Text.


Import Text

Importing External Text into AutoCAD.

Find/Replace Tab

We can find text in multiline text editor and replace or editing the text .

Properties Tab

Use the properties tab to specify the format of the entire paragraph Although this is the

second tab, it is recommended that you format the entire paragraph(s) here before editing

individual characters using the Character tab ( Figure. 6.16 ). The following options are

available.

Figure 6.16

Style

Choose from a drop-down list of existing text styles.

Justification

This property determines how the paragraph is located and direction of flow with respect to

the text boundary.


Width

Previous paragraph widths used are displayed in this drop-down list. You can enter a new

value in the edit box to change the width of the existing text boundary. If a Width of 0 is

entered or “no wrap” is selected, the lines of text will not “wrap” within the text boundary.

Rotation

The entire paragraph can be rotated to any angle. Changes made here are not reflected in the

text appearing in the editor but only in the drawing itself. You can type MTPROP at the

command line to directly access the Properties tab of the Multiline Text Editor.

Character Tab

After formatting the entire paragraph, use the character tab to alter individual characters in

the paragraph(s) ( Figure 6.17 ). using the option in this tab, first select ( highlight ) the

desired character or words, then set the desired options. The following options are available.

Figure 6.17

Font

Choose from any font in the drop-down list. Your selection here overrides the text Style

used for the entire paragraph(s). Even though you can change the font for the entire Mtext

object (paragraph), it is recommended to set the paragraph to the desired Style (in the

Properties tab), rather than changing all characters to a different font here. See following

NOTE.


Height

Select from the list or enter a new value for the height of selected words or letters. Your

selection overrides the text Height used globally for the paragraph.

Bold, Italic, Underline

Select (highlight) the desired letters or words then PICK the desired button. Only authentic

TrueType fonts (not the AutoCAD-supplied .SHX equivalents) can be bolded or italicized.

Stack/Unstack

If creating a stacked fraction, use a / (slash) between the numerator and denominator. If

creating stacked text, place a ^ (caret) before the bottom text. Highlight the fraction or text,

then use this option to stack or unstack the fraction or text.

Text Color

Select individual text, and then use this drop-down list to select a color for the selected text.

This selection overrides the layer color.

Symbol

Common symbols (plus/minus, diameter, degrees) can be inserted. Selecting Other...

produces a character map to select symbols ( Figure 6.18 ).


Figure 6.18


ACTIVITY 6B

ANSWER THE FOLLOWING QUESTIONS:

6.3 What is the difference between ‘Dtext’ and ‘Text’.

6.4 Create a Title Block

i. Begin a New drawing and assign the name TBLOCK. Create the title block as shown in

Figure 6.19 or design your own, allowing space for eight text entries. The dimensions

are set for an A size sheet. Use Pline with 0.02 width for the boundary and Lines for the

interior divisions. ( No Lines are needed on the right side and bottom because the title

block will fit against the border lines. )

Figure 6.19

ii. Insert test similar to that shown in Figure 6.20. Examples of the fields to create are:

Company or School Name

Part Name or Project Title

Scale

Designer Name

Checker or Instructor name


Figure 6.19

6.5 Create the text below using Multiline Text Editor with Font = RomanC and Height = 0.2

After that adjust the text as shown in Figure 6.20

Impact

RomanC

Height = 0.36

ArialArial

Figure 6.20


FEEDBACK TO ACTIVITY 9B

ANSWERS.

6.3 Text - Text is essentially the same as Mtext except that the text is not dynamically

displayed one letter at a time as you type, but rather appears in the drawing only

after pressing Enter.

Mtext - Multiline Text ( Mtext ) has more editing options than other text commands.

We can apply underlining, color, bold, italic, font, and height changes to individual

characters or words within a paragraph or multiple paragraphs of text.


QUESTION 6-1 : ANSWER ALL THE QUESTIONS BELOW.

a)

i. Create New drawing. Use Style to create a new style using the romans.shx font.

Use whatever justification methods you need to align the text information (not

the titles) as shown in Figure 6.21.

ii. Next, type the Style command to create a new style that you name as ROMANS-

ITAL. Use the romans.shx font file and specify a 15 degree obliquing angle. Use

this style for the NO., PART NAME, and MATERIAL. SaveAs BILLMAT.

Figure 6.21


b) Open the CBRACKET drawing from unit 5 ( Activity 5c ). Using romans.shx font,

use Dtext to place the part name and METRIC annotation (Figure 6.22 ). Use a

Height of 5 and 4, respectively, and the Center Justification option. For the notes,

use Mtext to create the boundary as shown. Use the default Justify method (TL) and

a Height of 3. Use Ddedit or Ddmodify if necessary. SaveAs CBRACTXT.

Figure 6.22


Feedback To Self-Assessment


E2004/7/1 DIMENSIONING

DIMENSIONING

UNIT 7

OBJECTIVES

General Objective : To understand the concept of dimensioning and usage of

dimensioning tools.

Specific Objectives : At the end of the unit you will be able to:

Create linear dimensions with DIMLINEAR,

DIMCONTINUE, DIMBASELINE, DIMALIGNED.

Create radial dimensions with DIMDIAMETER and

DIMRADIUS.

Create Angular dimensions with DIMANGULAR.

Create Ordinate dimensions with DIMORDINATE.

Create and edit the dimensions.


INPUT 7a

7.0 INTRODUCTION

As you know, drawings created with CAD systems should be constructed with the same

dimensions and units as the real-world objects they represent. The important of this practice is

evident when you begin applying dimensions to the drawing geometry in AutoCAD. The features

of the object that you specify for dimensioning are automatically measured, and those values are

used for the dimensioning text. If the geometry has been drawn accurately, the dimensions will be

created correctly. The correct use of AutoCAD dimension tools is the key to producing clear and

concise measured drawings.

AutoCAD provides a whole range of dimensioning tools which can be used to quickly dimension

any drawing without the need for measurement. Dimensioning in AutoCAD is automatic; lines,

arrows and text are all taken care of by the dimension commands. AutoCAD dimensions are

special blocks which can easily be edited or erased as necessary.

AutoCAD provides lots of control over the way dimensions look. Using a system similar to text

styles, dimension styles allow you to design dimensions so that they look just the way you want

them to.


Figure 7.1

For example, Figure 7.1 above shows two different dimension styles. The one on the left is the

default style known as STANDARD. If you do not create a style of your own or modify the

standard style, all dimensions will look like this. The dimension line has arrow heads and the

dimension text is positioned above the line and is drawn using the current text style. The

dimension on the right has been drawn using a new style. The arrows have been changed to

obliques, the vertical alignment of the text has been centered and the current text style has been

changed.

AutoCAD divides dimensions into four main categories: Linear, Radial, Ordinate and Angular.

When you create dimensions, AutoCAD automatically creates a new layer called "Defpoints".

This is a special layer which cannot be deleted or renamed. AutoCAD uses this layer to store

dimension information and you can effectively ignore it.

When working with dimensions it is very important that line origins are picked accurately so that

the resulting measurement and text are correct. Always use an Osnap to pick dimension line

origins.


7.1 SELECTING DIMENSION COMMANDS

Selecting and working with the dimension commands in AutoCAD R14 is much easier than in

previous versions. All commands can be accessed from the keyboard and now most commands

are also available from the Dimension pull-down menu and the Dimension toolbar. The

Dimension toolbar is particularly useful because it places all the dimension commands a single

mouse click away. Since the Dimension toolbar is not displayed by default you will need to

enable it from the Toolbars dialogue box.

To display the Toolbar dialogue box, select

Pull-down menu :View/Toolbars

Command : Toolbar

To display the Dimension toolbar, click in the

checkbox against "Dimension" in the toolbar list.

Figure 7.2: Toolbars Box

The main components of a dimension are

1. Dimension line

2. Extension lines

3. Dimension text

(usually a numeric value )

4. Arrowheads or tick marks

Figure 7.3


Dimensioning an object correctly requires a number of difference dimensioning methods

based on the object you are dimensioning. This includes:-

1. Linear methods for horizontal and vertical.

2. Aligned.

3. Angular method for angles.

4. Diameter and Radius methods for circles and arcs.

5. Ordinate method for datum-based.

7.2 THE LINEAR DIMENSION COMMAND

As the name suggests the Linear dimension commands are used to dimension along straight lines.

There are five linear dimension commands, namely: DIMLINEAR, DIMCONTINUE,

DIMBASELINE, DIMALIGNED and DIMROTATED. The DIMLINEAR command is

probably the most common dimension command you will use.

7.2.1 The Linear Dimension

Toolbar :

Pull-down :Dimension/Linear

Keyboard :DIMLINEAR

You can use this command to generate horizontal and vertical dimensions. Creating a linear

dimension is easy. All you have to do is start the command, specify the two points between which

you want the dimension to be drawn and pick a point to fix the position of the dimension line.

Consider the Figure 7.4 whilst working through the following examples.


Figure 7.4

Command Sequence

Command: DIMLINEAR

First extension line origin or press ENTER to select: (pick P1)

Second extension line origin: (pick P2)

Dimension line location (Mtext/Text/Angle/Horizontal/Vertical/Rotated): (pick a point to position

the dimension line, you will see the dimension rubber banding)

You may have noticed that the first prompt asks you to pick the first extension line origin or to

press the ENTER key. Pressing the Enter/Return key results in the following prompt:

Select object to dimension:

AutoCAD allows you to dimension an object simply by picking it. Try this out. Draw a line or a

circle and use this option rather than the two point option to see what happens.

Figure 7.5


Dimensions will automatically adjust themselves to accommodate most situations. For example,

the Figure 7.5 shows what happens to a dimension if the gap between the two extension lines is

too small for the dimension text.

7.2.2 The Continue Dimension

Toolbar

Pull-down Dimension/Continue

Keyboard DIMCONTINUE

You can use the Continue command to add a string of dimensions. In the Figure 7.4 the "36mm"

dimension has been continued from the "64mm" dimension.

Command Sequence

Command: DIMCONTINUE

Specify a second extension line origin or (Undo/<Select>): (pick P3)

Specify a second extension line origin or (Undo/<Select>): (pick another or to end)

There is no prompt for the first line origin, AutoCAD automatically selects the second line origin

of the previous dimension to be the first of the new dimension.

There is also no prompt for the dimension line position, AutoCAD automatically matches up with

the previous dimension.

Figure 7.6

Using the Continue command you can very quickly generate a string of dimensions which align

perfectly. In the example above ( Figure 7.6 ), the "34.41" dimension was drawn with the


DIMLINEAR command; all the other dimensions were drawn using the DIMCONTINUE

command and simply picking the four points, one after the other. You can only continue a

dimension in a single direction. To generate the "26mm" dimension in Figure 7.6, you will need

to use the DIMLINEAR command and pick P3 and P4 or Enter at the first prompt and pick the

line.

7.2.3 The Baseline Dimension

Toolbar

Pull-down Dimension/Baseline

Keyboard DIMBASELINE

You can use this command to generate a series of dimensions from a single base point. You must

already have created the first dimension in the sequence using a command such as DIMLINEAR.

The DIMBASELINE command then creates further dimensions in a similar way to the

DIMCONTINUE command. All the user has to do is pick points.

Command Sequence

Command: DIMBASELINE

Specify a second extension line origin or (Undo/<Select>): (pick next point)

Specify a second extension line origin or (Undo/<Select>): (pick another or Enter to end)

Select base dimension: (Enter again to end)


Figure 7.7

In the Figure 7.7, the "35.07" dimension was created using the DIMLINEAR command. The

others were created using DIMBASELINE and picking points 1 and 2.

7.2.4 The Aligned Dimension

Toolbar

Pull-down Dimension/Aligned

Keyboard DIMALIGNED

You can use this command to generate aligned dimensions. These are dimensions along inclined

lines, which cannot be dimensioned with the DIMLINEAR dimension command because that

command will only give a measured dimension in either a horizontal or vertical direction.

However, as you can see from the command sequence below, this command works in exactly the

same way.

Command Sequence

Command: DIMALIGNED

First extension line origin or press ENTER to select:(pick P1 at Figure 7.8 )

Second extension line origin: (pick P2 at Figure 7.8 )

Dimension line location (Mtext/Text/Angle): (pick a point)


Figure 7.8

The DIMCONTINUE and DIMBASELINE commands can both be used in conjunction with

DIMALIGNED dimensions.

7.3 THE RADIAL ( CIRCLE / ARC ) DIMENSION COMMAND

There are two main radial dimension commands, DIMDIAMETER and DIMRADIUS. Both

commands result in a similar looking dimension so AutoCAD automatically inserts a "R" to

indicate a radius and the dimension symbol to indicate a dimension. You can get AutoCAD to

display the dimension symbol by including "%%c" in any text string. For example, in order to

draw the 40mm diameter text as it is shown in the illustration Figure 7.9, you would need to type

"%%c40mm". You can use this special character with any of the text commands.

Figure 7.9


The Diameter and Radius commands are supplemented by the DIMCENTER command, which

can be used to add a center mark to any circle or arc. The DIMDIAMETER and DIMRADIUS

commands do not automatically draw a center mark.

By convention it is usual to dimension full circles using a diameter and arcs (partial circles) using

radius.

7.3.1 The Diameter Dimension

Toolbar

Pull-down Dimension/Diameter

Keyboard DIMDIAMETER

Figure 7.10

You can use the Diameter command to annotate a circle or an arc with a diameter dimension. To

achieve this simply start the command, pick a point on the circumference of the circle, pick a

second point to determine the length of the leader and then add the dimension text or Return to

accept the default.

Command Sequence

Command: DIMDIAMETER

Select arc or circle: (pick the circumference P1 in Figure 7.9)

Dimension line location (Mtext/Text/Angle): (move the cursor until you are happy with the text

position and then pick to complete the sequence)


7.3.2 The Radius Dimension Command

Toolbar

Pull-down Dimension/Radius

Keyboard DIMRADIUS

Figure 7.11

The Radius command is identical to the Diameter command except that the dimension

measurement is a radius rather than a dimension and the resulting dimension text is prefixed with

a "R" to indicate radius.

Command Sequence

Command: DIMRADIUS

Select arc or circle: (pick the circumference P2 in Figure 7.9 )

Dimension line location (Mtext/Text/Angle): (move the cursor until you are happy with the text

position and then pick to complete the sequence)

Notice that in the Figure 7.11 the radius dimension has been positioned inside the circle. Both

diameter and radius dimensions can be positioned either inside or outside an arc or circle.

Practice with the Radial and Diameter commands until you understand how they work.


7.3.3 The Center Mark Command

Toolbar

Pull-down Dimension/Center Mark

Keyboard DIMCENTER

Figure 7.12

You can use the Center Mark command to annotate a circle or an arc with a cross at the center.

The Figure 7.12 shows a center mark added to a circle after a diameter has been drawn.

Command Sequence

Command: DIMCENTER

Select arc or circle: (Pick the circumference of a circle or arc)

A cross is drawn at the center point.

7.4 ANGULAR DIMENSIONS

There is only one command in this section and it is used to annotate angular measurements.

The Angular Dimension Command

Toolbar

Pull-down Dimension/Angular

Keyboard DIMANGULAR

Figure 7.13


The Angular command is amazingly flexible and can be used to indicate an angle in almost any

situation. Just like the other dimension commands, all parts of the process are rubber banded so

you can see the results of your actions before you make the final pick.

Command Sequence

Command: DIMANGULAR

Select arc, circle, line, or press ENTER: (pick a line)

Second line: (pick another line)

Dimension arc line location (Mtext/Text/Angle): (pick point)

Move the cursor position until you are happy with the result. Notice that you can move the cursor

to either side of the lines and the angular dimension will change accordingly.

Figure 7.14

You may have noticed that at the first prompt you are given the option to press ENTER. If you use

this option you will be prompted to pick the angle vertex and then the two angle endpoints. This is

quite useful if the angle you need to dimension is not defined by physical lines on the drawing.

The illustration on Figure 7.14 shows the result of this option. The centre point of circle 1 was

picked as the angle vertex and the centre points of circles 2 and 3 were picked for the two angle

endpoints.

The degree character is automatically inserted for you, however, if you ever need to type it, you

can do so by typing "%%d". This is another of AutoCADs special characters.


7.5 ORDINATE DIMENSIONS

Ordinate dimensions are not really dimensions at all in that they do not indicate a measurement.

Rather they annotate known co-ordinate points. The DIMORDINATE command is used to

indicate the X and Y ordinate values at any point.

The Ordinate Dimension Command

Toolbar

Pull-down Dimension/Ordinate

Keyboard DIMORDINATE

The Ordinate command is used to annotate co-ordinate points with X or Y values. This may be

useful for setting-out on site plans.

Command Sequence

Command: DIMORDINATE

Select feature: (pick the point to annotate)

Leader endpoint (Xdatum/Ydatum/Mtext/Text): (pick endpoint or use one of the options)

By default a vertical leader will display the X ordinate and a horizontal one will display the Y

ordinate. However, you can use the Xdatum and Ydatum options to override this default. In the

Figure 7.15 , the building corner on the left has been annotated with X and Y ordinates using the

default method.

Figure 7.15


The one on the right has a Y ordinate, which has been forced to display in a vertical position

using the Ydatum option. You could also use the Text or Mtext options to clearly describe the

point you are annotating.

7.6 ANNOTATION WITH LEADERS

Ordinate dimensions are not really dimensions at all in that they do not indicate a measurement.

Rather they annotate known co-ordinate points. The DIMORDINATE command is used to

indicate the X and Y ordinate values at any point.

The Leader Command

Toolbar

Pull-down Dimension/Leader

Keyboard LEADER

Figure 7.16

The Leader command can be used to annotate any point on a drawing. The command sequence

below was used to draw the leader shown in the Figure 7.16.

Command Sequence

Command: LEADER

From point: (pick the point to annotate)

To point: (pick vertex point)

To point (Format/Annotation/Undo)<Annotation>: (pick end point)

To point (Format/Annotation/Undo)<Annotation>:

Annotation (or press ENTER for options): Corner of

MText: building

MText: (to end)


Unlike other dimension commands the leader and annotation text are drawn as separate objects.

So, if you need to move or edit the text, you can do so without affecting the leader line.

As you can see by the command line, there are a number of options with this command including

"Format" options which include "Spline". Experiment with these options until you understand

them.


ACTIVITY 7a

ANSWER ALL THE QUESTIONS.

7.1 Give FIVE ( 5 ) component of dimension?

7.2 State the technique for dimension?

7.3 Draw the figure below with dimensioning. Use Start From Scratch> English setting.

Please use all the dimensioning technique that we have learned.

Figure 7.17


PLATE 0.25 mm

Figure 7.18

Figure 7.19



ANSWERS.

7.1 The components of a dimension are

Dimension line

Extension lines

Dimension text (usually a numeric value )

Arrowheads or tick marks

7.2 Technique for dimensioning

Linear methods for horizontal and vertical

Aligned

Angular method for angles

Diameter and Radius methods for circles and arcs.

Ordinate method for datum-based

Another question, please draw carefully and after finished, please discuss with your own

lecture


INPUT 7b

7.7 EDITING DIMENSIONS

The dimension edit commands, DIMEDIT and DIMTEDIT are used primarily to adjust the

position of the text part of a dimension. This is usually only necessary if the drawing is quite

complex and the dimension would read more clearly if it were in a different position.

7.7.1 The Dimension Text Edit Command

Toolbar

Pull-down Dimension/Align Text/ ( Choose your options )

Keyboard DIMTEDIT

The Dimension Text Edit command is used to modify the text position of any single dimension.

The command can be used to position the text dynamically (this is the default) or one of the

options can be used for a specific type of movement. For example, the dimension shown on

Figure 7.20 has been modified by dynamically moving the position of the text and then the text

has been rotated using the Angle option.

Figure 7.20


Command Sequence

Command: DIMTEDIT

Select dimension: (pick the dimension you want to edit)

Enter text location (Left/Right/Home/Angle): (pick a new position or use an option)

Figure 7.21

The results of the four available options are shown in the Figure 7.21.

The Left option moves the text to a left justified position within the dimension.

The Right option moves the text to a right justified position within the dimension.

The Home option returns the text to the home position after it has been modified.

The Angle option enables the text to be rotated about its center.

7.7.2 The Dimension Edit Command

Toolbar

Pull-down Dimension/Oblique (other options are duplicated in DIMTEDIT so don't appear)

Keyboard DIMEDIT

The Dimension Edit command can be used to modify and change the text of any number of

dimensions. The command could, for example, be used to add a standard prefix or suffix to a

number of dimensions.


Command Sequence

Command: DIMEDIT

Dimension Edit (Home/New/Rotate/Oblique) <Home>: (choose an option)

Select objects: (pick one or more dimensions)

Select objects: (pick more or end)

The command sequence will vary depending upon which option has been chosen but the results of

the various options are illustrated in Figure 7.22

Figure 7.22

The Home option returns dimensions to their home position.

The New option displays the Multiline Text Editor. The changes you make to the text will be

applied to all selected dimensions so it is important not to delete the "<>" marker from the text

string. Deleting this marker will remove the values from all selected dimensions.

The Rotate option can be used to rotate dimension text about its center point. It works in exactly

the same way as the Angle option of the DIMTEDIT command except that you can rotate any

number of dimensions at once.

The Oblique option is used to set the dimension lines at an angle. This option can be very useful

when you are dimensioning a drawing in isometric projection (see Figure 7.23 ). In this case the

drawing has been dimensioned using the Aligned command and then the oblique angle modified

to suit the dimension position. This usually means setting an angle of 30, 330 or 90 degrees

depending upon the dimension orientation. If you are creating details in isometric projection make

sure you are using the isometric snap/grid option for greater efficiency.

http://www.cadtutor.net/acad/acadr14/dims/dims.html#aln


Figure 7.23

7.8 DIMENSION STYLES

Dimension styles are the main method used to control the way dimensions look. Using styles you

can change the text font, the arrow head style, the relative position of the text, the scale of

dimensions and many other parameters. Styles are created using the DIMSTYLE command.

Dimension styling is a relatively complex area of AutoCAD and the finer points are beyond the

scope of this unit. However, the main points which will enable you to create clear, good looking

styles are set out below.

7.8.1 The Dimension Style Command

Toolbar

Pull-down Dimension/Style…

Keyboard DDIM short-cut D

The Dimension Style command can be used to change the appearance of dimensions. The best

method is to create a new style before you start creating dimensions so that you can leave the

STANDARD style as a default option. Having created a new style from STANDARD, then you


can apply any modifications you generally require to the parent style and then more specific

modifications to the child styles in order to create a style family.

Name Edit Box

Figure 7.24

Dimension styles are created using the Dimension Styles dialogue box. The dialogue box is

shown on Figure 7.24. As you can see from the dialogue box, a style is applied to a family of

dimensions. By default, any style changes are made to the parent. Each style parent has six child

styles. The child styles, Linear, Radial, Angular, Diameter, Ordinate and Leader can be used to

modify the parent style when that particular type of dimension is used.

For example, you may like to use a tick rather than an arrow head for your dimensions but

this isn't really appropriate for a leader, so the Leader child style can be changed so that leaders

will always be drawn with an arrow head whilst all other dimensions of the same style family are

drawn using ticks.


7.8.2 Creating a New Style

To create a new dimension style, make sure the STANDARD style is the current style, click in the

Name edit box and type the name of the new style you wish to create. Click the Save button. You

will see a message in the lower left corner of the dialogue box which says "Created name from

STANDARD" where name is the new style name which you typed. The new style is

automatically set as the current style. You may rename the new style if you wish, simply by

typing a new name in the Name edit box and clicking on the Rename button.

The new style which you have created is identical to the STANDARD style, so you must now

modify your new style so that it can be used to create dimensions which conform to your own

requirements. Style changes are made in three categories, Geometry, Format and Annotation

( Figure 7.25 ). As you can see from the Dimension Styles dialogue box, each category is

represented by a button which leads to a dialogue box which is used to modify the settings in that

particular category.

Figure 7.25


7.8.3 Setting the Arrow Head Type

The style of arrow heads is set using the Geometry dialogue box, illustrated in Figure 7.26. As

you can see, the STANDARD style has Closed Filled arrow heads as a default. To change the

arrow head style for a new dimension style, make sure the style is current and that the "Parent"

radio button is selected (this assumes you are not modifying a child style), click on the

"Geometry…" button and select a new arrow head type from the "1st" drop-down list. Once

selected the new arrow type is illustrated in the dialogue box. If you require different arrow heads

at each end of your dimensions you can set the other type using the "2nd" drop-down list. Click

on "OK" to return to the Dimension Styles dialogue box.

Figure 7.26

7.8.4 Dimension Scale

When you are working with drawings, which will be plotted, at different scales, you will need

some way of changing the scale of the dimension lines relative to your drawing so that they

always appear the same size, irrespective of plotting scale. You can achieve this by using the

Scale variable. This option is also available from the Geometry dialogue box. The default value is

set to 1.0. The larger the value the larger the dimension will appear.

For example, a value of 2.0 would double the text height and the arrow size. To change

the scale of dimensions, simply type the required scale in the "Overall Scale" edit box. Try

changing the scale factor and check the results. The scaling applies to individual styles, so you

could create different styles with different dimension scales to be used for different plotting

scales.


Note that changing the scale of dimensions does not affect the dimension value, this is always

calculated in drawing units.

7.8.5 Setting the Text Location

To change the text location click on the "Format…" button in the Dimension Styles dialogue box.

The Format dialogue box is shown in Figure 7.27. By default the horizontal justification is set to

"Centered" and the vertical justification to "Above". This means that the dimension text will

appear centered above a horizontal dimension line and centered left of a vertical dimension line.

To have the text cantered within the dimension line, click on the down arrow of the "Vertical

Justification" pull-down list to reveal the options and click on "Centered". The illustration

changes to reflect your choice. Click on "OK" to return to the Dimension Styles dialogue box.

You can see the result of this action by looking at the illustration below. Experiment with the

Horizontal Justification and Vertical Justification options to see what results they give.

Figure 7.27


You can also use Text the option in this dialogue box to change the text orientation in aligned

dimensions. By default all dimension text is aligned with the dimension. This option allows you

to force text to appear horizontal, irrespective of the orientation of the dimension. You have

independent control over dimension text which appears inside and outside of the dimension lines.

The illustration on the Figure 7.28 shows a dimension with vertical justification set to "Above"

( left) and to "Centered" (right).

Figure 7.28

7.8.6 Setting Text Style and Units

Text style and units are both set using the Annotation dialogue box, illustrated in Figure

7.29 To set a text style to a dimension you must first have created the style using the Text Style

command (Format/Text Style… from the pull-down menu). To assign the text style to a

dimension style, click on the "Annotation…" button in the Dimension Styles dialogue box, click

on the drop-down list in the "Text" area of the Annotation dialogue and select the required text

style from the list. Click on "OK" to return to the Dimension Styles dialogue.

AutoCAD gives you the option to automatically include a unit prefix or suffix with the

dimension text. For example, you could set the dimension style in such a way that it created

dimensions with "m" to indicate meters after each dimension text. Most usually, dimensions are

drawn without units displayed but with a note on the drawing indicating the units used, such as

"All dimensions in meters". However, you may have a drawing where different units are being

used for different elements of the drawing.


Figure 7.29

In such a case it is a good idea to include units to avoid confusion. Remember that the main idea

behind dimensioning is to give the maximum amount of information in the clearest and most

concise way. To add units to a dimension style, click on the "Annotation…" button in the

Dimension Styles dialogue box and enter the required unit character(s) in the "Prefix" and/or

"Suffix" edit boxes of the "Primary Units" area of the dialogue box. For example, if you wanted to

display meters, you would type "m" in the "Suffix" edit box.


7.9 THE DIMENSION UPDATE COMMAND

Toolbar

Pull-down Dimension/Update

Keyboard DIM UPDATE

The Dimension Update command is used to apply the current dimension style to existing

dimensions. You can use this command to change the style of a dimension. Unlike text styles,

dimension styles do not automatically update when the style is changed. The UPDATE command

must be used to force dimensions to appear in the current text style.

Command Sequence

Command: DIM

Dim: UPDATE

Select objects: (pick dimension to update)

Select objects: (pick more dimensions or to end)

Dim: (press the escape key, Esc to return to the command prompt)


ACTIVITY 7b

ANSWER ALL THE QUESTIONS.

7.4 Draw the following figure using the dimension given.

Figure 7.30


Figure 7.31



Check the completed drawing with your lecturer.


EXERCISES.

Question 7-1 :

a) Draw the figure below with dimension given.

i)

Figure 7.32


ii)

Figure 7.33



Check your drawing with your lecturer.

E 2004/9/1 Printing & Plotting

UNIT 9

PRINTING AND PLOTTING

OBJECTIVES

General Objective : To understand and apply the Printing and Plotting setting.


List the typical steps for printing or plotting.

Invoke and use the Print / Plot Configuration dialog box.

Select from available plotting devices and set the paper size.

Specify the area of the drawing to print or plot.

preview the print/plot before creating a plotted drawing.


INPUT 9a

9.0 INTRODUCTION

AutoCAD display drawing in two ways, as hard copies or soft copies. A soft copies

is the view of drawing shown in the drawing window. AutoCAD uses pixels to convert into

the images seen on your monitor. A hard copy is the plotted or printed version on your

drawing on paper. AutoCAD produces hard copies by converting data into a raster or vector

image that is read by a printer or plotter. Hard copies are generally used for finalized

drawing or for drawing reviews. Hard copies can be scaled, unscaled, or real life

representation of your work.

9.1 Print / Plot Configuration

Plotting and printing are accomplished from within AutoCAD by invoking the Plot

command. Using the Plot or Print command invokes the Print/Plot Configuration dialog box

( figure 9.1 ). You have complete control of plotting and printing using the dialog box. In

AutoCAD, the term “plotting’ can refer to plotting on a pen plotter and/or printing with a

printer.


figure 9.1 : Print/Plot Configuration dialog box

Typical step to plotting / Printing.

Assuming the CAD system has been properly configured so the peripheral devices ( plotter

and/or printers) are functioning, the typical basic steps to printing and plotting using the

Print/Plot Configuration dialog box are listed below:

1. Use Save to ensure the drawing has been saved in its most recent form before

plotting ( just in case some problem arises while plotting).

2. Make sure the plotter or printer is turned on, has paper and pens loaded, and is ready

to accept the plot information from the computer.

3. Invoke the Print/Plot configuration dialog box.

4. Check the upper left corner of the dialog box to ensure that the intended devices

have been selected. If not, select the Devices and Default Selection tile and make the

desired choice.

5. Check the upper right corner of the dialog box to ensure the desired paper size has

been selected. If not, use the Size…. tile to do so.

6. Only when necessary, change other option such as Rotation and Origin and Pen

Assignments.

7. Determine and select which area of the drawing to plot : Display, Extend, Limits,

Window or View.

8. Enter the desired scale for the print or plot. If no standard scale is needed, toggle

Scale To Fit ( so the check mark appear in the box )


9. Always Preview the plot to ensure the drawing will be printed or plotted as you

expect. Select either a Full or Partial preview. If the preview does not display the

plot as you intended, make the appropriate changes. Otherwise, needless time and

media could be wasted.

10. If everything is OK, selecting the OK tile causes the drawing to be sent to the plotter

and printer.

11. For additional plots or prints, you can use the Preview command to preview and plot

the drawing based on the parameters previously set in the Print/Plot Configuration

dialog box.

9.2 Using the Plot / Print Command

Methods for opening the Print / Plot Configuration dialog box include:

Toolbar :

Menu : File > Print

Command : Plot

The Print / Plot Configuration dialog box will displayed as shown in figure 9.1.

Devices and Default Selection

The Devices and Default Selection option lets you review current information on the

configuration of plotters and printers. When you select the Devices and Default Selection

button, the Devices and Default selection dialog box is displayed. This section describes the

uses of the Select a Device, and the Device specific configuration areas found in the dialog

box. You cannot add a device to the dialog box at this stage. You must reconfigured

AutoCAD to recognize another plotter. The dialog box is shown below.


Figure 9.2 : Device and default Selection Dialog Box

The show and change option in the Device Specific Configuration areas lets you review or

change the printer/plotter setting. A description of these options follows:

• Show - when the show button is chosen, the Show Device

Requirements dialog box is displayed with information about the current

printing devices. This dialog box is shown in the following figure:

Figure 9.3 : Show Device Requirement Dialog Box

• Change - If you want to change information about the printer/plotter,

choose the change button. The dialog box that is displayed is determined by

the type of printer/plotter currently being used. For examples, if you choose

the Change button, the Change Device Requirements dialog box may be

displayed. However, another printing device may display the Print Setup


dialog box. Each of these dialog boxes require you to enter different

information to change the printer/plotter setting.

Figure 9.4 : Print Setup Dialog Box

Pen Parameters

The Pen Parameters areas of the Print / Plot Configuration dialog box lets you change pen

parameter settings. The Pen Assignment button, and the Optimization button are located in

this area. Choosing the Pen Assignments button opens the Pen Assignments dialog box

containing the following option:

• Color - displays the AutoCAD color to which you assign a width, pen.

speed, or linetype. If you have a single pen plotter, and have chosen the

option to plot different colors with different colored pen, AutoCAD pauses

when necessary during the plot and issues a prompt let you to stop and

change the pen.

• Pen - pens are used with pen plotters. This option lets you assign a

color to a pen number.

• Ltype - displays the linetype number assigned to the current color. To

see the available plotter linetype, check the Feature Legend button.

• Speed - this option is used to assign plotting speed to pens used with

pen plotters. Each plotting speed is assigned a color.


• Width - the width option display the line width assigned to a color.

This option generally determine the line width of lines drawn with raster

printer.

Figure 9.5 : Pen Assignment Dialog Box

The optimization button located in the Pen Parameters area, displays the Optimizing Pen

Motion dialog box. This dialog box has a list of check boxes that increase optimization, by

minimizing wasted pen motion and reducing plotting time. By default, AutoCAD minimizes

pen motion when a drawing is plotted. With the exception of the No Optimization button,

the more button are checked the higher the optimization. The printer or plotter determines if

the options in dialog box are available. The Optimizing Pen Motion dialog box is displayed

in the following Figure 9.6:

Figure 9.6 : Optimizing Pen Motion Dialog Box


Additional Parameters.

The Additional Parameters area of the Print / Plot Configuration dialog box has a list of

options used to properly setup your drawing for printing and plotting. The following list

describes each of these options:

• Display - this option prints or plots everything shown in the current

view of the drawing window.

• Extents - this option plots the area of the drawing that contain objects.

Before you print or plot the drawing, use the Zoom to Drawing Extent option

to make sure include all the object you have created.

• Limits - this option prints or plots everything located inside the

established drawing limits.

• View - this option lets you plot an existing named view. When you

select the View button the View Name dialog box is displayed. Select the

name view you want to plot, then choose OK. The Print / Plot Configuration

dialog box is redisplayed with the view check box highlighted.

• Window - this option lets you specify the rectangular you want to plot,

print or save to plot files. When this button is selected, the Window Selection

dialog box is displayed. You can enter coordinates for the first Corner and

Other Corner in the dialog box, or use the Pick button to define a window in

the drawing. After you specify the plot area choose the OK button. The

Window checkbox is now checked. The Window Selection dialog box is

shown in Figure 9.7:

Figure 9.7 : Window Selection dialog box


• Text Resolution - this option sets the resolution value for printed text.

Lower values increase the plotting speed, but decrease the resolution. Higher

values decrease the plotting speed, and increase the resolution. This also sets

the resolution, in dot-per-inch, of True Type font while plotting. This value

is stored in the TEXTQLTY system variable.

• Text Fill - if selected, this option displays some text as a solid or filled

objects. If the box is unchecked the latter are plotted in an outline form.

• Hide-Line - this option if checked, plots model space view with hidden

line removed when a drawing is plotted.

• Adjust Area Fill - this option lets you compensate for pen-width when

plotting wide polylines, solid-filled traces or filled 2D solid. AutoCAD adjust

the boundary of filled areas inward by half a pen width. This can be

important for exacting applications like printed circuit board artwork that

require greater accuracy.

• Autospool - this option lets you send a plot file to a printing device while

you continue to work. For more information check the Online Help.

• Plot to file - the Plot To File option lets you create a plot file. Many

applications such as word processors can include AutoCAD plot file as

illustration. Instead of printing or plotting your drawing, you have the option

of generating files with .plt file name is the drawing name. When this button

is checked the File Name button is activated.

• File name - when the File Name button is selected, the Create Plot File

dialog box is displayed. This dialog box lets you name the plot file, then save

it to a specified directory. After you assign a name and directory, choose the

Save button. The Create Plot File dialog box is displayed in the following

Figure 9.8:


Figure 9.8 : Create Plot File Dialog Box

Paper Size and Orientation.

The Paper Size and Orientation area is used to determine the size of the paper that will be

used for plotting. You can also select the plot specification units. This is done by choosing

Inches or the MM button for millimeters. The Paper Size and Orientation area also have a

Size button, Orientation icon, and Plot Area line. These features are discussed in the

following section:

Size

The type of printing device that you use determines if the Size button is activated. If the

box is not shaded you can select the Size button. The Paper Size dialog box is then

displayed. You will find a list of standard paper size in the window on the left side of the

dialog box. To change the paper size, select one of the rows.

AutoCAD also lets you create your own paper size by entering numbers at the User lines.

This is done by selecting the Width and Height boxes and entering the desired sizes. To add

the new paper size to the window, move the cursor inside of the window and press the left

mouse button once, or press ENTER. The new paper size is then displayed. When a paper

size is selected the assigned name is displayed next to the Size button in the Paper Size and

Orientation area.


Orientation

When a paper size is selected the Orientation icon and name are displayed in the Paper Size

dialog box. The Orientation icon is also shown in the Paper Size and Orientation area. The

icon changes depending on the plotting device configuration. The orientation can be

Landscape, which means in a horizontal position, or Portrait which is a vertical position.

Plot Area

This line displays the numbers used to create the current paper size. When you are plotting ,

the paper size ( plot area ) dimensions used by AutoCAD and the printing device may not be

consistent. This can result in plotted drawing that do not fit on the paper. For example HP

plotter have wide margins which often cut into the effective plot area.

Scale, Rotation and Origin.

The scale, Rotation and Origin area have options that are used to help you plot drawing that

meet certain specifications. The plot image is always aligned with the lower left corner of a

specified plot area, even when plot is rotated. When a plot is offset, the offset is applied to

the entire plot image, rather than the plot origin point. The plot image is offset away from

the lower left corner on the page. A description of the options are:

Rotation

If you select the Rotation and Origin button, the Plot Rotation and Origin dialog box is

displayed. The Plot and Rotation area of this dialog box lets you select the rotation angle of

the plotted drawing. The rotation angle can be set at 0, 90, 180, 270 degree.

Origin

The Plot Origin area of the Plot Rotation and Origin dialog box lets you change the origin of

the plot. Generally all drawings are printed from the 0,0 origin located in the lower left

corner of the paper. If you want your plot to start in a new location, enter the new coordinate

values at the X origin and Y origin edit boxes. This lets you place multiple plots on the same

sheet. The Plot Rotation and Origin dialog box is shown in the following Figure 9.9


Figure 9.9 : Plot Rotation and Origin

Scale

Scale factor is used to print or plot text, dimensions, tick marks, arrow and drawings at the

proper size. After you determine your scale factor, AutoCAD lets you enter a scale in the

Plotted Inches = Drawing Units and the Plotted MM = Drawing Units edit boxes. To use

this option, make sure the Scale to Fit button is not selected.

Scale to Fit

If you do not have a scale factor, select the Scale to Fit option. AutoCAD then adjusts the

drawing to fit inside of the selected paper size boundaries. This is done by calculating the

ratio between the width and height of your specified drawing area and the width and height

of the plotted area. The scale factor set by AutoCAD will be displayed in the Plotted Inches

= Drawing Unit and the Plotted MM = Drawing Units edit boxes.

Previewing a Plot

The Plot preview area lets you review your drawing before it is printed or plotted. You can

select a Partial or Full preview by selecting an option button then choosing Preview. These

options are described in the following sections.

Partial

When the Partial button is selected the Preview Effective Plotting Area dialog box is

displayed. This dialog box lets you see your drawing in relation to the current paper size.

The paper dimensions are found below at the Paper Size line. The blue outline represents

your drawing. The dimension of your drawing are located at the Effective area line. If the


paper size and effective area are the same dimensions, the outline will have a red and blue

dashed line around it.

If there are problems with the orientation of the drawing and the paper size, a warning is

displayed at the bottom of the Preview Effective Plotting area dialog box. The most

commonly displayed commands are:

• Effective area too small.

• Origin forced effective area off display.

• Plotting area exceed paper maximum.

If any of these items are displayed, you may need to adjust the plot setting then preview the

drawing again. This ensures that your drawing is set up properly before it is printed or

plotted. The dialog box also has a Rotation icon located inside of the red and blue outline

areas of the dialog box. To determine the rotation angle observe the icon location. Each

angle is assigned a location which includes : 0 bottom-left corner, 90 top-left corner, 180

top-right corner, and 270 bottom-right.

The Preview Effective Plotting Area dialog box is displayed in the following Figure 9.10

Figure 9.10 : Preview Effective Plotting Area.


Full

The full preview option lets you see the drawing as it would be displayed on paper. When

this option is selected a 0-100% meter is displayed at the bottom of the Print/Plot

Configuration dialog box. When the regeneration is complete the drawing is displayed,

while a regeneration takes place and the PLOT command process the data. To end the Full

preview option, Press ESC. ENTER, or the right mouse button to activate the Realtime PAN

and ZOOM menu. This menu lets you use the PAN and ZOOM commands to change the

view or location of the plotted image on the display screen. The following figure

demonstrates how a drawing would be displayed after a full preview.


ACTIVITY 9a

EXERCISES.

9.1

i) Open the drawing from Program File, ( C : \ Program File \

AutoCADR14 \ Sample \ Watch ).

ii) Invoke the Print / Plot Configuration Dialog Box. Set the Additional

Parameter to Limits. Click on the Devices and Default Selection Box and

click Change at Device Requirement.

iii) When the Print Setup Dialog Box appeared, set the paper size to A4 and

Orientation to Portrait.

iv) Click OK and see the result.

9.2

i) Open the drawing from Program File, ( C : \ Program File \

AutoCADR14 \ Sample \ opera).

ii) Invoke the Print / Plot Configuration Dialog Box. Set the additional

parameter to Extents. Click on the Devices and Default Selection Box

and click Change at Device Requirement.

iii) When the Print Setup Dialog Box appeared, set the paper size to A4 and

Orientation to Portrait.

iv) Click OK and see the result





QUESTIONS 9-1 :

a) What is the function of Pen Parameter dialog box and what are the options

contain?

b) Open the Schematic Diagram from Draw Command unit (Figure 4.37) that you

have done before. Print the drawing to A4 size and Portrait Orientation.

c) Open the office floor plan drawing you have done in unit 8, Print the drawing to

A4 size and Landscape Orientation.



ANSWERS

QUESTION 9-1

a) Pen Parameters

The Pen Parameters areas of the Print / Plot Configuration dialog box lets you

change pen parameter settings. The Pen Assignment button, and the Optimization

button are located in this area. Choosing the Pen Assignments button opens the Pen

Assignments dialog box containing the following option:

• Color - displays the AutoCAD color to which you assign a width, pen

speed, or linetype. If you have a single pen plotter, and have chosen the

option to plot different colors with different colored pen, AutoCAD pauses

when necessary during the plot and issues a prompt let you to stop and

change the pen.

• Pen - pens are used with pen plotters. This option lets you assign a

color to a pen number.

• Ltype - displays the linetype number assigned to the current color. To

see the available plotter linetype, check the Feature Legend button.

• Speed - this option is used to assign plotting speed to pens used with

pen plotters. Each plotting speed is assigned a color.

• Width - the width option display the line width assigned to a color.

This option generally determine the line width of lines drawn with raster

printer.

E2004(auto cad)

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